eBook Computer Repair for PC Owners Ver 1.01

8/8/2019 eBook Computer Repair for PC Owners Ver 1.01

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E-book edition Version 1.01

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CESAR A BALLADARES

Electronic Engineer

ComputerRepair for

PC Owners

Cesar A Balladares

[email protected]

Hardware: Networking, desktop repair andnotebook repair.

Software: Windows XP, Windows Vista,Windows 7 and Linux.

Level:Beginners to intermediate.

http://www.techbooks.books.officelive.com/http://www.techbooks.books.officelive.com/http://www.techbooks.books.officelive.com/


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ii

About the author

Cesar A Balladares holds a bachelors degree in ElectronicEngineering and a Post Degree in Telematics both from the National

University of Engineering, Nicaragua. He is an expert in the field ofcomputers and computers networks. He has been involved withcomputers since 1990.

The author was born in Nicaragua. Some years ago, a communistdictatorship took the power of the country. The communists forced himinto exile, he moved to the USA in the year 2000.

Note to the E-book edition

The e-book edition is a pre-edition of the printed version aim tofuture buyers, reviewer, editors and publishers. The e-book edition is foredition and marketing purposes and the content can be different incomparison to the final printed version.

If you are reading this version and you believe that something iswrong or that something can be improved, pleased do not hesitate incontact me directly.

I must warn that this e-book only has some selected chapters taken

from different sections of the printed edition. Some sections such assafety, tools and troubleshooting are not present in this e-book. Therefore,the content of this e-book edition will not give you enough knowledge inorder to repair a computer for yourself.

The printed version of this book use a hand on approach with a lo tof interaction and step-by-step guides for resolve hardware and softwareproblems. I recommend buy the printed edition if you want repair hardwarecomponents or manipulate software.

Finally, I recommend using the printed edition of the book in order

to get a fully understanding of safety procedures, tools andtroubleshooting techniques.The author is not liable or responsible for anyloss or damage arising from information contained in this e-book.

Note: Content in color blue only appear in the E-book edition.


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Dedication

To my motherRosa Blanco Gonzalez

R.I.P

Tell me what you think!

As a reader, you are the most important critic and commentator ofmy books. I value your opinion and want to know how I could do it better.I look forward your comments and advices. You can contact me by

e-mail at the following address:

[email protected]

Cesar A Balladares

Where can I buy a copy of this

book?

You can order a copy of this book at your preferred bookstore. Youcan also buy a copy of this book directly at


You can also get a free e-book with some selected chapters at

mailto:[email protected]://www.techbooks.books.officelive.com/http://www.techbooks.books.officelive.com/mailto:[email protected]


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Trademark Acknowledgment

The author has made every attempt to supply trademarkinformation about company names, products and services. The author

cannot attest accuracy in trademark information.

Many of the pictures uses in this book have been taken frombrochures, manuals and public information such as consumers forums ormanufacturers support pages. The author cannot claim ownership in anypicture taken from a commercial product or from a private web site, mostpictures used in this book are public content but others are licensed andhave been made available for this publication. In the Internet, licenses andcopyrights sometimes get misapplied. Therefore, if I have taken somethingof yours that is copyrighted or I have not acknowledged your authorship,send me an email, and I will promptly remove the offending material infuture publications.

The author made most of the diagrams but some diagrams havebeen taken from others sources. The pictures and diagrams informationare exposed at the final of the book.

Warning and DisclaimerThis book was written in order to provide valuable information and

advice to the people who want repair and upgrade PCs. Every effort hasbeen made in order to provide accurate information but no warranty is

implied.

The information is provide as is basic. The author is not liable orresponsible for any loss or damage arising from information contained inthis book.

If you are reading the e-Book edition please read Note to the e-book edition.

CopyrightCopyright 2010 Cesar A Balladares, 531 NW 44 AVE, Miami, FL

33126. All rights reserved. No part of this publication may be stored in aretrieval system, transmitted, or reproduced in any way, including but notlimited to photocopy, photograph, magnetic, or other record, without theprior agreement and written permission of Cesar A Balladares.
mailto:[email protected]:[email protected]


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Sections at a Glance

1 Getting Started1.1 Introduction1.2 Brief history of computers1.3 Working with computers1.4 Hardware and Software2 Hardware2.1 PC Components2.2 Motherboards2.3 Microprocessors2.4 Memory2.5 Hard Drives2.6 Optical Drive2.7 Power supply and Batteries2.8 Input Devices2.9 Monitors2.10 Video cards2.11 Sound Cards2.12 Cases2.13 Printers and scanners2.14 Flash memories2.15 MP3 Players2.16 Digital Cameras3 Software

3.1 Operative Systems3.2 Installing Windows3.3 Installing Linux3.4 Software Applications3.5

Working with Windows XP

3.6 Working with Windows Vista3.7 Working with Windows 73.8 Working with Linux Ubunto3.9 Installing Multiple Operative Systems


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4 Networking4.1 Computer Networks4.2 Networks Installation4.3 Network and Internet Configuration4.4 Modems and Faxes4.5 Using the Internet5 PC Maintenance5.1 Cleaning PCs5.2 Backing-Up Information5.3 Computer Tune-up5.4 Antivirus and Security

6 Troubleshooting6.1 General Problems6.2 Hardware Problems6.3 Software Problems6.4 Data Recovery6.5 System Recovery7 Your New Computer7.1 Buy a new computer or build a new one?7.2 Buying a new computer7.3 Building your own computer7.4 For new PC owners8 Appendix8.1 Bits and Bytes8.2 Numerical System9 Photographs and Illustrationscredits

10 Index


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Table of Contents

Only chapters with page numbers appear in the E-Book

version. In order to access the whole book you must buythe printed edition.

1 Getting Started

1.1Introduction

1.1.1 How to use this book ........................................................................ 21.1.2 What is a computer? ....................................................................... 41.1.3 Different types of computers ............................................................ 4

1.2Brief history of computers

1.2.1 Mechanical Calculators .................................................................... 51.2.2 Mechanical Computers .................................................................... 61.2.3 Electronic Computers ....................................................................... 81.2.4 The Personal computer.................................................................... 9

1.3Working with Computers1.3.1 Electricity1.3.2 Safety1.3.3 Basic Tools1.3.4 Intermediate Tools for PC Repair1.3.5 Networking Tools1.3.6 Software Tools1.3.7 Data Recovering Tools1.3.8 Cleaning Tools

1.4Hardware and Software

1.4.1 What is Hardware1.4.2 What is Software


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2 Hardware

2.1PC Components

2.1.1 Desktop External Parts .................................................................. 142.1.2 Desktop Internal Parts.................................................................... 162.1.3 Laptop Internal parts ...................................................................... 172.1.4 Laptop External parts ..................................................................... 19

2.2Motherboards

2.2.1 What is a Motherboard? ............................................................... 202.2.2 Motherboard form factors ............................................................. 222.2.3 Chipset ......................................................................................... 222.2.4 Processor Sockets ....................................................................... 22

2.2.5 Memory Slots ............................................................................... 232.2.6 Expansion card Slots ................................................................... 242.2.7 Bios Chip ...................................................................................... 272.2.8 Disk drive connectors ................................................................... 322.2.9 USB and Firewall connectors ...................................................... 332.2.10 Power connectors ........................................................................ 362.2.11 I/O connectors .............................................................................. 392.2.12 Keyboard and Mouse connectors ................................................ 412.2.13 installing a new motherboard ....................................................... 42

2.3Microprocessors

2.3.1 Processors History ........................................................................ 452.3.2 Math Processor .............................................................................. 482.3.3 Clock Speed ................................................................................... 482.3.4 Data I/O bus ................................................................................... 492.3.5 Internal registers ............................................................................. 502.3.6 Address bus.................................................................................... 502.3.7 Cache memory ............................................................................... 51

2.3.8 Processor sockets .......................................................................... 512.3.9 Heatsinks and processors fans ..................................................... 542.3.10 Installing a new processor ............................................................. 56


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2.4Memory

2.4.1 RAM ............................................................................................... 602.4.2 Different types of RAM .................................................................. 612.4.3 Memory Category ......................................................................... 61

2.4.4 Memory Types .............................................................................. 632.4.5 Memory Standards ....................................................................... 642.4.6 Memory Speed ............................................................................. 652.4.7 Memory Size ................................................................................ 662.4.8 Installing desktop memory ............................................................ 682.4.9 Installing notebook memory .......................................................... 70

2.5Hard Drives

2.5.1 What is a hard drive

2.5.2 Hard drives History2.5.3 Bits and Bytes2.5.4 IDE interface2.5.5 SATA Interface2.5.6 Formatting hard drives2.5.7 Hard drives barriers and RAID2.5.8 Installing desktop hard drives2.5.9 Installing notebook hard drives2.5.10 Boot Process

2.5.11 External Hard Drives

2.6Optical Drives

2.6.1 Optical Storage2.6.2 CD-ROMs2.6.3 DVD ROMs2.6.4 IDE optical drives2.6.5 SATA optical drive2.6.6 Installing desktop optical drives

2.6.7 Installing notebook optical drives2.6.8 External optical drives


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2.7Power supply and Batteries

2.7.1 Introduction to Power supply2.7.2 Electrical Recommendations2.7.3 Changing your power supply

2.7.4 Installing Power supplies2.7.5 Notebook Power2.7.6 Notebook Batteries2.7.7 Protection and UPS

2.8Input devices

2.8.1 Keyboards2.8.2 Mice2.8.3 Trackballs

2.8.4 Touchpads and Input Tablets2.8.5 Touch Screens2.8.6 Games controllers and Joysticks2.8.7 Port replicators2.8.8 KVM

2.9Monitors

2.9.1 Displays history2.9.2 Monitor specifications2.9.3 Types of monitor2.9.4 CRT2.9.5 LCD2.9.6 Plasma2.9.7 Touch screen Monitors2.9.8 TV as monitors2.9.9 Monitor connectors2.9.10 Choosing a new monitor2.9.11 Installing a new monitor


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2.10Video cards

2.10.1 What is a video card?2.10.2 Video card history2.10.3 Video card Memory

2.10.4 Video card connectors2.10.5 Video Capture cards2.10.6 Multiple monitors2.10.7 Video card interfaces2.10.8 Choosing a new Video Card2.10.9 Installing a new video card

2.11Sound Cards

2.11.1 What is a sound card?

2.11.2 Sound card history2.11.3 Multimedia2.11.4 Sound card components2.11.5 MIDI Interface2.11.6 Sound card connections2.11.7 Recording2.11.8 Speakers2.11.9 Installing sound cards and speakers

2.12Cases

2.12.1 What is a compute case?2.12.2 Case form factors2.12.3 Computer case components2.12.4 How to buy a computer case


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2.13Printers and scanners

2.13.1 What is a printer?2.13.2 Different types of printers2.13.3 Printing media

2.13.4 Printer consumables2.13.5 Printer Communications2.13.6 Printer Properties2.13.7 Printing documents2.13.8 Scanners2.13.9 Printers as a copy and fax machine2.13.10 Photo programs2.13.11 Buying a new printer2.13.12 Installing a new printer

2.14Flash memories

2.14.1 What is a flash memory?2.14.2 USB Flash drives2.14.3 Memory cards2.14.4 Flash memory accessories2.14.5 How to use flash memories

2.15MP3 Players

2.15.1 What is a MP3 player?2.15.2 MP3 players history2.15.3 Media formats2.15.4 Getting music from the internet2.15.5 Sound and video editors2.15.6 Buying a new MP3 player2.15.7 How to use an MP3 player


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2.16Digital Cameras

2.16.1 Digital cameras2.16.2 Types of digital cameras2.16.3 Web cameras2.16.4 Camcorders2.16.5 Camera connectors2.16.6 Image file formats2.16.7 Photo and Movies programs2.16.8 Camera functions and specifications

3 Software

3.1Operative Systems

3.1.1 What is an operative system?.................................................... 723.1.2 Operative System components ................................................. 733.1.3 Family of operative Systems ...................................................... 763.1.4 MS-DOS ..................................................................................... 763.1.5 Microsoft Windows ..................................................................... 783.1.6 Linux ........................................................................................... 803.1.7 Apple Mac OS ............................................................................ 823.1.8 Choosing an Operative System ................................................. 83

3.2Installing Windows

3.2.1 Preparing the hard drive ............................................................ 843.2.2 Installing Windows XP ............................................................... 853.2.3 Installing Windows Vista3.2.4 Installing Windows 73.2.5 Using Restore CDs3.2.6 After Installing Windows

3.2.7 Installing drivers for Windows XP3.2.8 Installing drivers for Windows Vista and Windows 7


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3.3Installing Linux

3.3.1 What is Linux Ubunto?3.3.2 Different ways to install Linux Ubunto3.3.3 Installing Linux Ubunto

3.3.4 Installing drivers for Linux Ubunto

3.4Software Applications

3.4.1 What is a Software application?3.4.2 Types of software applications3.4.3 Getting software3.4.4 How to install software applications

3.5Working with Windows XP3.5.1 Introduction of Window XP3.5.2 The desktop3.5.3 Windows XP Basic3.5.4 Managing files3.5.5 Control Panel

3.6Working with Windows Vista

3.6.1 Introduction of Window Vista

3.6.2 The desktop3.6.3 Windows Vista Basic3.6.4 Managing files3.6.5 Control Panel

3.7Working with Windows 7

3.7.1 Introduction of Window Vista3.7.2 The desktop3.7.3 Windows Vista Basic3.7.4 Managing files3.7.5 Control Panel


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3.8Working with Linux Ubuntu

3.8.1 Introduction of Ubunto3.8.2 The desktop3.8.3 Linux Ubunto Basic

3.8.4 Installing Ubunto Applications

3.9Installing Multiple Operative Systems

3.9.1 Why install multiple operative systems in the same PC?3.9.2 Multiple operative system configurations

4 Networking

4.1Computer networks

4.1.1 What is a Computer Network? ....................................................... 944.1.2 Types of Computer Networks ........................................................ 954.1.3 Network Architecture ...................................................................... 964.1.4 Network Topologies ........................................................................ 974.1.5 Network Protocols .......................................................................... 984.1.6 Network standards ........................................................................ 99

4.2Network Installation

4.2.1 Networks Components ............................................................... 1004.2.2 Networks Interface Card (NIC) ................................................... 1014.2.3 Cables.......................................................................................... 1044.2.4 Connectors .................................................................................. 1084.2.5 Techniques for buildin your own twister pair cables4.2.6 Installing Home Wired Networks4.2.7 Installing Home Wireless network

4.2.8 Installing Structured Networks4.2.9 Powerline networking4.2.10 PC to PC files transfer


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4.3Network and Internet Configuration

4.4Modems and Faxes

4.5Using the Internet

5 PC Maintenance

5.1Cleaning PCs

5.2Backing-Up Information

5.3Computers Tune-Up

5.4Antivirus and Security

6 Troubleshooting

6.1General Problems

6.2Hardware Problems

6.3Software Problems

6.4Data Recovery

6.5System Recovery

7 Your New Computer

7.1Buy a new computer or build one?

7.2Buying a new computer

7.3Building your own computer

7.4For new PC owners


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8 Appendix

8.1Bit and Bytes

8.2Numerical System

9 Photographs and Illustrationscredits

10Index


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GETTING STARTED

1.1 Introduction

1.2 Brief history of computers

1.3 Working with computers

1.4 Hardware and Software

Section

1


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1.1 Introduction

1.1.1 How to use this book

Sixty years ago, you needed have a PhD in Physic or Mathematics in order to understand what acomputer can do. We have advance so much since then. Now we use computers all time. We use computers atwork, in the school and in every moment of our life.

We have learned how to use the computer but many people still have numerous problems with them. Ihave been involved with computers for twenty years and I have fixed hundred of PCs. I must confess most ofthe computers problems are easy to fix. Everybody with some knowledge in computers can resolve most of theproblems.

The objective of this book is to teach the PC owner how to repair his PC. In this book I will teach howthe PC works, how they can be fixed and how keep them running. One important thing about this book is that

you will learn how to repair and how to use the computer, for example, besides teach you how to repair aprinter I will teach how you can use the printer. I dedicated many parts of the books in teaching the use ofhardware components and software applications. I think you need learn to use your computer before you triedto repair it.

I produced this book thinking in the people that can use a computer but do not have any idea in howto fix it. Therefore, if you never in your life have opened a PC, if you do not know the difference betweenhardware and software, this book is for you. Most of the work in this book refers to desktop computers,but we are going to study how repair notebooks too.

The first section of this book is an introduction of the computer history, some people think that

computers were invented 15 years ago, others think the Internet and Windows have always been part of thecomputers. In the first section, you will learn that computer science have been part of human history forthousands of years and that computers today are quite different of computers some years ago.

The second part of this book is hardware; I will teach about the different components that computershave how to install them and how to repair them. In the hardware section I will talk about the different devicesa PC owner use with the computers such as MP3 players and digital cameras; In my opinion these devices arepart of the computer and people must now how to work with them.


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The third section of this book is software. I know that many people that own computer do not have adeep knowledge of Windows. I will begin this chapter with a small introduction of operative systems. I will talkabout Windows XP, Windows Vista and Windows 7 and then I will give an introduction of Linux. At the endof this section I will include some basic techniques in how install many operative system in the same computer

The fourth section is about computer network. I will explain what a computer network is and which

component a computer network has. I will explain computer networks installation and configuration. Finally, Iwill talk about the Internet.

The fifth section is about PC maintenance. I will teach some techniques and procedures in how keepyour computer without problems.

The sixth section is about troubleshooting, this section is a guide to resolve computers problem. I willteach software and hardware troubleshooting.

In the seven and last section, we are going to compare the advantages and disadvantages of building acomputer by yourself. Then we will build a computer from scratch. I will give you tips, recommendations andstep-by-step pictures of the construction. We will have a complete working PC system. At the end of this

chapter, I will give some recommendations for people that just bought a new computer.

After you read this book you will have the knowledge to resolve commons problems in the areas ofhardware and software, you will be able to do PC maintenance, upgrades and build your own computer system.

Since the computer is a changing industry, you really will never finish learning; there always will be anew technology, a new operative system or a new technique you will need to learn.

As a final point, you must be aware that repair computers is a technique, the knowledge that you obtaindepend in great part of the time that you spend fixing a computer. Although this book offer you a theoreticalguide, hands on practice and real life problem solution is what will teach you the most.

Now that you know how this book is designed, we can begin our study of computers. In order to fix acomputer there are some important concepts that you must learn.


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1.1.2 What is a Computer?

It is very difficult to give an exact definition of what a computeris. At the beginning, computers weremachines that helped resolve mathematical problems. Now the computer realizes manipulation of data, thisdata could be numbers, words, music, pictures etc. In the last years, we have seen a merge of the computerswith the telecommunications and entertainment.

One simple definition of computer is, computer is a programmable machine that store and manipulate digital data.Computer can be mechanical or electronic and the data can be stored using mechanical gears, magneticmaterial or transistors.

Although computers have existed for thousands of years, the first electronic computer was invented inthe mid 20th century. For many decades, computers were used only for military, business and academicpurposes. PC or personal computer was developed in massive scale in the early 80s.

1.1.3 Different types of computers

There are many kind of computers and many way of classified them. We can classified a computer by

Architecture: Mac or PC

Operative Systems: Windows, Mac or Linux

Processor: Intel or AMD

Size: Desktop, Laptop or netbook

There are a lot of architectures, processor and operative systems but the studies of these topics arebeyond the scope of this book. There are also computers such as the mainframes or supercomputers used byuniversities, governments, etc. We also have the Mac family of computer. Several of these computers areclearly superior of a PC nevertheless is not the objective of this book to cover them.

In this book, I will focus my attention to the PCs; these are the mass consumers computers. I amtalking about the computer you see in electronic store such as IBM, DELL, Gateway, HP, etc. Thosecomputers possible use Windows and they can be upgraded and fixed very easy.

I will be give emphasis to Windows base computers and Windows problems but I will do an

introduction to Linux operative systems.


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1.2 Brief history of computers

1.2.1 Mechanical Calculators

The development of the computer is linked to the history of the humanity. Since the invention of the

mathematics, humankind has had the need of counting. With the past of the time, this counting becomesmore difficult and then the man invented ways to perform complex calculations.

One of the first machines that humankind uses for counting was the abacus. The abacuswas used forseveral centuries. Many ingenious machines were developed like the astrolabe. TheAntikythera Mechanismfromabout 150-100 BC is considered the first single purpose analog computer. The castle clock from 1206 was thefirst programmable single purpose computer.

Abacus and astrolabe, early computing mechanism

Many automatic machines were built in the antique world. Until the renaissance, most devices werecalculator or single purpose machine. In the XIX the first multipurpose programmable computer werecreated.


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Antikythera Mechanism, the first single purpose computer Original and reconstruction

1.2.2 Mechanical Computers

The industrial revolution paves the development of mechanical computers. Analytics machines werebuilt in the XIX century. In this time the first computer programs were created, it was the born of theprogramming and computer science. In this period many machines were build. The most important develop inthis time was the Analytic MachinebyCharles Babbage, this was the first programmable mechanical computer.The construction of this machine began in the year 1837 but never finished. Although many machines werevery advance none was build for commercial use.

Babbage Difference Machine Analytical Engine


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The beginning of the XX century brought a vast amount of data and the necessity of manipulate thisdata. In order to control this information new ways of storing and computing the data was needed. IBMspearheaded the develop of computer using new inventions like the punched cards, Boolean algebra and laterthe vacuum tube. It was the beginning of the commercial computer.

Early IBM Tabulating Machine 1890


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1.2.3 Electronic Computers

In 1936Alan Turinthe father of the computer science, formulate the concept of algorithm and designthe modern computer architecture, his model is still use in computers today. The invention of the vacuumtubestarted the development of the electronic computers in the 40s and 50s. Generally, only the government andthe military could afford those machines.

The invention of the transistorwas the key in the developed of the mainframes and business computersin the 60s. A lot of big business bought those machines generally for accounting and payroll. The inventionof the ICmarked the introduction of the personal computer in the 70s.

ENIAC first general purpose electronic computer build in 1946

The electronic computer progress follows the development of these electronic devices:

Vacuum tubes (40s and 50s): Vacuum tubes were the first electronic amplifier.

Transistors (60s and 70s): Transistors were the first solid-state amplifier, and successor of thevacuum tube.

Integrate circuits or IC (70s): IC is a technology which consist in integrate many electroniccomponents like transistors, diodes, capacitors and resistors in one package.

Processor (from the 80s to today): Processors are electronic devices composed of a control unit,arithmetic-logic unit an instruction-decoding unit.


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IBM407 computer from 1953

1.2.4The Personal computer

What is a personal computer? The term personal computer refers to a computer designed for anindividual use. From the mid 40s to the 70s the peopled used mainframes.Mainframes werehuge and expensivecomputer owned by the government and big corporations, hundreds of staff members ran them, therefore there were nopersonal. No individual person owned a computer; a computer in that time was like a space rocker today, huge,complex and expensive.

In the decades of the 70s the development of the processor made possible the miniaturization andposterior commercialization of the home computers, at the beginning these computers where sold by mail andthey arrived as do for yourself kits, only technicians could ensemble them. At the end, you had a wood boxwithout operative system, monitor, keyboard or mouse.

The computers had buttons instead of keyboard and little lights instead of monitor. The users had toinvent their own operative systems and programs therefore; no everyone could use these devices. In the early70s these build by yourself computers were called home computer.


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Altair is considered the first line of personal computer but was Apple the firstcompany that introduced a computer cheap enough for mass consumer.

Altair 8800 from 1975 one of the first microcomputers

Apple II from 1977

The invention of the microprocessor in the early 70s paved the way of theintroduction of the microcomputers in the late 70s and early 80s. In 1977 Applelaunched one of the first successful commercial microcomputers the Apple II, the mainconsumer target in that time were middle and small business and not individuals. Thepersonal computers from late 70s were called microcomputers; this term was used formore than 10 years.


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REPAIR

FOR

PC

OW

NERS

1

IBM responded to the success of the Apple II with the launch of the IBM PC in1981. The introduction of the IBM PC was a great success; therefore, two companiesleaded the market in this time, Apple and IBM.

The Apple operative system was the Apple DOSit was used only with Applecomputers. The IBM operative system was the PC-DOSnevertheless; an almost identicaloperative systemMS-DOSwas available for any computer manufacturer.

In that time many manufacturers like Wang, HP and Compaq launched their ownline of personal computers. In order to use the successfully Microsoft DOS operativesystem all these companies copied the IBM hardware, these family of computer wereknow as IBM compatibles.

The original IBM PC model 5150 from 1981

The development of the Intel processor brought us the Intel architecture and theproduction of the 286, 386,486 and Pentium processors. Intel processors were the key inthe development of the PC hardware. The introduction of MS-DOS and later Windowsoperative system marked the beginning of the use of computer for the general people.Microsoft software played a key role in the development of the PC software althoughWindow like applications were used for Apple computers long time before Windows.

In the early 90s most manufacturers were IBM compatibles, companies likeDELL, Compaq, HP controlled the marked. In this time almost all computers usedWindows and Intel processors, it was the beginning of the Wintel architecture. Wintel wasthe technology responsible of the development of the computers since the early 90s.


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Today a big share of the computer marker belongs to clones. A clone iscomputer build with parts of different companies, a clone company does not build they

own hardware they only assemble computers parts then sell the whole product undertheir brand.

After this introduction, some reader can wonder why the people still call mostcomputers PC, after all PC is really the line of IBM personal computers build in the early80s. Most of the times the term PC is used for describe a no Apple computer, whichmeans if it is no Apple is a PC. I prefer the old term, a personal computer is a computerdesigned in order to satisfy the needs of a person and not a group.

The computer become personal thanks of the shrinking and falling of prices ofthe processors and memories, those advances make possible the mass production ofcomputers. PC are cheaper every day and now they are a just a gadget like a phone or

TV.

The merger between computers and entertainment brought us the MP3 players,DVDs and digital cameras. The blending of computers and telecommunication hascreated new forms of computing like the Internet, social networks and the smartphones.The advances in electronic have given computers power to almost all electronic devices.We can find computers in the auto, in the phone and in most appliances.

We can say; Computers today are beyond doubt personal.

You can continue reading the rest of the section inthe printed edition of this book.


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13

2.1 PC Components2.2 Motherboards2.3 Microprocessors2.4 Memory2.5 Hard Drives2.6 Optical Drive2.7 Power supply and Batteries2.8 Input Devices2.9 Monitors2.10 Video cards2.11 Sound Cards2.12 Cases2.13 Printers and scanners2.14 Flash memories2.15 MP3 Players2.16 Digital Cameras

Section

2


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2 .1 PC Components

2.1.1 Desktop External Parts

A desktop computer is the kind of computer you set in a desk; generally, it cameseparate in modules such as system unit, monitor, keyboard, mouse, etc. The desktopcomputer is the first generation of personal computers. The objective of this section is tohave a first look of the desktop computer and connections. The following pictures showus what a desktop looks like.

Monitor System Unit

Keyboard Mouse

Desktop computer.

The System Unit is the PC main part; here is where the processor, memory andhard drive are located. Here is a typical system unit with all its parts.

System Unit front view.


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Older computers used to have the USB port and audio connectors at the back,now all the models have these connectors at the front, sometimes there are covers withsmall doors. If it is possible, try to identify the connections in your own computer.

System Unit rear view.

Modern computer lack of dedicate keyboards and mouse connectors instead theyused the USB port for connect the keyboard and mouse.

You can note the colored plugs at the back of the computer, for example, greenfor speakers and pink for microphone, the color of the keyboard and mouse connectorsare respectively purple and green.


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2.1.2 Desktop Internal Parts

In this section you can observe what you will find when you open a desktopcomputer. In the picture, we can observe the System Unit interior; we can see themotherboard, the memories, the power supply, the hard drive and the optical drive.These are the typical parts in every computer.

If you feel ready, you can now open your PC following the safety procedureslike unplug the power. Try to identify the components in your own PC withouttouching or removing anything.

System Unit inside view.

The advantage of repair and upgrade computers is that the parts come inmodules. Therefore, if you for example need more memory or a bigger hard drive, you

can buy some memory modules or a new hard drive and install them in the computer.

When you need repair a computer, most of the times it is easy to buy a newpart and discharge the old one. It is no worthy trying to fix a CD drive, a mouse or akeyboard. Laptop computers have the same parts that a desktop have but in most cases,there are more difficult and expensive to repair.


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2.1.3 Laptop External parts

Laptops computers are portable computer, these kinds of computers arebecoming very popular. Like their desktop counterparts, they have parts that can berepaired, or upgraded.

Other name that a laptop receives is notebook. Generally, a laptop is moreexpensive than a desktop with the same specs nevertheless their size allowed a greatversatile. In recent years majority of sales in the PC have been laptops.

If you are a laptop owner, try to identify your laptops parts and connectors.

Laptop computer external view


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You can note that in laptops computers, the screen and keyboard are embedded inthe device, therefore it is very difficult exchange screen and keyboard among laptops, andgenerally, you must order the parts from the manufacturer.

Laptop computer connectors

Recently we have seen a new device called netbook, a netbook is a cheap laptopwithout CD ROM, low memory, slow processor and small hard drive. These devices are

more suitable for internet browser and light applications. The price and size have madethese devices very popular.

Laptop computer have connectors like the desktops, it is very easy connect andexternal monitor, keyboard or mouse to a laptop. Some laptops have port replicatorsconnectors; a port replicator is a connector that let connect the power, one monitor, onemouse, one keyboard and several accessories using only one cable.


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2.1.4 Laptop Internal parts

The procedures to disassemble notebooks varies in each notebook model, in thissection I want show you a first look of some internal notebook parts. If you feel right youcan now open the laptops cover in the bottom of your laptop, I want that you locate thehard drive and memory without taking them off or touch them.

Before serving a notebook, you must always unplug the power cord and removethe battery. If you try fixing a notebook without removing the battery first, you coulddamage it.

Laptop computer parts

Replacing a laptop memory, battery or hard drive is very easy. Other part like themotherboard is very complicate because you must literally take the whole laptop apart.

Every component inside a desktop computer is also present inside a notebookcomputer. Notebooks have motherboards, network cards, modems, optical drives, etc. In

the next chapters, we will study notebook components further.


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2.2 Motherboards

2.2.1 What is a Motherboard?

The motherboardis the circuit board where the processor, memory and expansioncards are located. The motherboard together with the processor is one of the mostimportant components in the computer. The motherboard also receives the name ofsystem board. In the next pictures, we can see a motherboard with all its parts.

Motherboard top view


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Motherboard Rear View

In the last pictures, we can see the typical components of the motherboard such as:

Chipset

Processor sockets

Memory Slots

Expansion card Slots

Bios Chip

Disk drive connectors

USB and Firewall connectors

Power connectors

I/O connectors

Keyboard connectors (Keyboard and mouse connectors are used lessevery time)


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2.2.2 Motherboard form factors

The motherboard physical size and slots position depends of theform factor. Therehave been a lot of different form factor, most of them are obsoletes now. Right now, the

most used form factor is the ATX. Some variant of the ATX exist like the EATX(extended ATX) and ATX (micro ATX).

Motherboard form factors

2.2.3 Chipset

The most important factor in a motherboard is the chipset. The Chipset is theinterface between the processor, the memory, expansion cards and others components ofthe motherboard. The chipset has several components such as the processor bus interfacecalledfront side bus or FSB,memory controllers, I/O controllers, etc. The chipset is not acomponent that you can exchange or upgrade like the processor or memory, the chipsetis the motherboard itself. If the processor is the brain of the PC, the chipset is thenervous system. The chipset determine what kind of processor or memory the computer

can have.

2.2.4 Processor Sockets

The processor socket is the motherboard part where the processor set. Everysocket can hold only a specific type of processors. Sockets vary in size, form and pinnumber, for example the Socket 1 has 169 pins and was designed for processor 486, whereas the socket 370 has 370 pins and was designed for processors Celeron andPentium III.

Every socket has a key, which consist in missed holes in one

or two corners. The processor has also a key, which consistin some missed pins in the corners. The holes much matchthe pins, in this way we can set the processor in the rightposition.

You will learn more about processor in the section 2.3processors.

Socket 370


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2.2.5 Memory Slots

The motherboard has two different types of memoryROM (Read Only Memory)and RAM (Random Access Memory). The ROM memory is a electronic chip with

information about the system, this information will not change. The RAMmemory isused when the computer run a program, that means in order to run a program someinformation has to be stored in the RAM memory. The information in the RAMmemory is changing continuously.

The RAM memory is one of the principal parts of the computer. The velocityof the computer will depend in how much memory it has, you must have the biggestmemory you can afford.

The memory slots are the physical connector where the memory chips are set.The memory bus transfer information between the RAM and the CPU.

Every motherboard has different slots numbers and size. There aremotherboards with two slots other have 4 or 8. The slots have different sizes dependingof the type of memory. Right now most of the memories have 240 pins, but we can findolder systems with memories of 204 or 184 pins.

Memory slots

We will study more about memory in the section 2.4 Memory.


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2.2.6 Expansion card Slots

Before talking about expansion card, we must know what a bus is. A Busis asignal pathway; the signal uses this pathway for carry information between componentsinside and outside the computer. There are different kinds of buses, but we will focus ourattention to the expansion bus.

The expansions bus is very easy to identify because it uses cards slots. In theseslots, we can connect the expansion cards. The expansion card is could be a modem, avideo card, a network card, a USB hub card, etc.

Card Slots

Expansion card slots

There many types of buses, the most popular is the PCI, the PCI bus has

developed in many subcategories like the PCIe and PCI-X.

PCI: The Peripheral Component Interconnectdeveloped some years ago in order toreplace the ISA bus. The PCI bus supports 32 and 64 bits data path. It is still very popularnevertheless; we can find superior buses like the PCIe and PCI-X.


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PCI-X: PCI-X is known as PCI expanded it is a doublewide version of the PCI,it has higher bandwidth and is used mainly in servers. Modern PCI card can be inserted inPCI-X connector but older PCI cards cannot. The PCI-X slot support many speeds thatmean some are fasters than others.

PCIe: PCIe is Known as PCI express or PCI-E, it was created recently forreplace the PCI and PCI-X. It is more popular every day; it comes in many sizes likePCie x1, PCie x4 or PCie x16. The x1 is the smallest and the x16 the biggest. Oneadvantage of this bus is that small cards can be fit in biggest slots, that mean you caninsert an x1 card in one x4 slot.

Expansion card slots

AGP:Stand for Accelerated Graphics Port. It is an old bus used for video card. Theslot is physically similar to the PCI but generally is darker in color. In the past, it was thestandard for video card but now the PCIe has replaced it.


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Laptop computers also use expansion buses in their design.

Mini PCI is based in the PCI but smaller. It is used in laptop computers.

Mini PCIe is based in the PCIe but smaller. It is used in laptop computerssince the year 2005 and is the replacement of the mini PCI.

Laptop Expansion cards

PCMCIA: PCMCIA is an expansion card for laptop computers, the namePCMCIA stand for Personal Computer Memory Card International Association. Thecard has been renamed lately to PC card. The card is about the size of a credit card.

The card has evolved in various types such as type I, type II and type III, everytype has a different size. Right now, it is used mostly for network cards, modems andhard drives.

PCMCIA TV

turner card, youcan watch TVin your laptopusing this card

PCMCIA or PC card


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2.2.7Bios Chip

So far, we have studied a little bit about hardware and software, we knowhardware is all the physical components inside a computer like hard drive, networks card,

etc, whereas software is the operative systems and programs. Since many hardwaremanufacturers use many software programs it must exist one way that allow hardwareand software communicate between them, this is done using the BIOS.

BIOS: It stands for Basic Input/Output System. This chip on the motherboardallows an operating system run the same application using different hardware. We mustvisualize a PC system like a system of layers; the most basic layer is the Hardware layer,above that is the BIOS Layer, then the Operative System layer and Finally the applicationLayer.

PC System of layers

In the last table, we can observe that a word application running in windows vistacan work with an AMD or Intel processor, the BIOS work like a translator between theoperative system and the processor.

APLICATIONS

Example: Word 2007

OPERATIVE SYSTEM

Example: WindowsVista

BIOS A

Example: HP BIOS

Hardware A

Example: AMDprocessor

APLICATIONS

Example: Word 2007

OPERATIVE SYSTEM

Example: WindowsVista

BIOS B

Example: Dell BIOS

Hardware B

Example: INTELProcessor


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The BIOS has information about many hardware devices like network cards,modems, DVD drivers, etc; as well as many operative system like windows XP orwindows Vista. This is the reason why you cannot run a Windows XP 64 bits with a 16bits processor because the BIOS cannot do the translation from software to hardware. It

is the same reason why sometimes you cannot run hardware for windows 7 in a computerwith windows XP.

Since the BIOS stand between the hardware and software it receive the name offirmware, the meaning of firmware has evolved dramatically in recent years. Firmware isbasically software embedded in a chip.

The BIOS depend of the manufacturer ofthe motherboard therefore, we have HPBIOS, DELL BIOS, Gateway BIOS, etc:

Many times the PC manufacturer use thirdpart BIOS like American Megatrends orPhoenix Technologies.

AMIBIOS

Some years ago, the BIOS cannot be updated, but now in modern PC you canupdate the BIOS, this let us use new hardware and new operative system features.Therefore, if you are installing a new hardware like a new video card sometimes you mustupdate the BIOS in order to take full advance of the hardware features.

Older BIOS cannot be upgraded because they used ROM chips, ROMstand forread only memory that means theirs content cannot be changed , now all BIOS usedEEPROMchips , EEPROM stand for electrically erasable programmable read-only memory; thatmeans the BIOS can be upgraded. Nevertheless, people continue call the BIOS ROMmemory. Sometimes people confuse BIOS with CMOS RAM.

CMOS RAM: The CMOS RAM is also a chip in the motherboard, and the realname is RTC/NVRAM or real-time clock/ nonvolatile memory. The name CMOSstandfor complimentary metal-oxide semiconductor, this is a family of chips. The name CMOSis appropriate because most of the chips today use CMOS technology.

Although the CMOS RAM chip stores the BIOS set up, the BIOS firmware isstored inside the BIOS chip. We are talking about two different chips.


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The CMOS RAM stored the BIOS set up information and setting such as.

Date and time

Drives information

Hardware information

Boot order

User password

In order to enter the BIOS set up you must restart the computer and during theboot processing press one key or a combination of keys. Usually the keys are F1, F2,Del, Esc or F10. Every computer is different; you can find the right combination in thecomputer manual. Sometimes you can also see a message like for example Press to

enter BIOS setup. In the appendix of this book, you can find some combination key formost computers.

System BIOS screen

Manipulate the bios information is not a good idea for students that arebeginning to learn how to repair a computer, therefore I will postpone the biosmanipulation for later sections.

We will learn to reconfigure the BIOS set up in many sections of the book likethe sections about hard drivers, video cards, operative system, troubleshooting andbuilding your own computer but first you must get a little bit more information abouthow a computer works.


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CMOS Battery: In order to keep all these information the CMOS need aconstant source of power, that is the reason a CMOS battery must be used, this battery isgenerally a regular CR2025, the same of many calculators. The charge in this battery lastapproximately 5 years, when it is discharge you must enter the CMOS information

manually every time you power up the system.

CMOS battery

We will study how resolve battery problems in the section of troubleshooting.

Password Protection: Almost all the CMOS set up have a section aboutPassword Protection, this password is wrote in the CMOS. When you power up a systemwith password protection, the first screen you see is the Set up screen asking you aboutthe password. If you do not write the password correctly, you cannot enter to the System.

We will study how to clear password in the section of troubleshooting.Note:The password in the Set Up is notthe same that the password in Windows.


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POST: Another important function handle by the BIOS is the POST or PowerOn Self test. The function of the POST is identified the computer components and setthem in such a way, the operative system can use them, here is a list of the POSTfunction.

Test the BIOS itself

Discover and test the computer hardware such as processors, hard drives,network cards, etc.

Verify memory

Test the buses

Discover expansion cards

The post also must identify if a system was turned off correctly. If all thehardware is good then the operative system will initialize. If there is something wrong inthe POST process, the Operative System will not start.

If something is wrong, the computer will show screen messages and sound aseries of beeps indicating the type of failure. These messages are generally some codeslike A1, DO or D3 every BIOS manufacturer have different codes therefore the code inone computer has a different meaning in another computer. The beeps are a series oflong and short beeps and they are very useful when you have problem with the videocard and you cannot see the codes in the monitor.

One tool that you can use for identified POST codes is the BIOS POST card,you can connect this car to the expansion bus and see the code with the help of someLEDs.

You can see the POST codes in the screen.

POST BIOS card


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2.2.8 Disk drive connectors

Computers use hard drive (HD) in order to storage information, in this momentthere are mainly two interfaces for connect hard drive inside a computer, there are:

ATAknow as IDE, Parallel ATA or PATA

SATAknow as Serial ATA

Older computer systems used ATA but now modern computer use mostly SATA. Another disk connector is the floppy disk (FD) connector, FD are obsolete knowtherefore we will not studied them in this book.

ATA connector

SATA connectors

Floppy connectors

Typical Motherboard with ATA, SATA and floppy connectors

In modern computer, you will find only one IDE connector and many SATAconnectors; older system generally had two IDE connectors. Usually you can connecttwo HD using one IDE connector but only one HD using one SATA connector.

Besides HD you can also connect CD drives and DVD drives, in recent years

many motherboard have external SATA connectors called eSATA which you can uselike an USB connector in order to connect a great variety of hardware like camcorder orexternal hard drives.

If you motherboard does not have build in SATA connector, you can use an IDEto SATA adapter or an expansion card with SATA connectors in order to use SATAdevices. I will talk about IDE and SATA configuration in section 2.5 Harddrives.


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2.2.9 USB and Firewall connectors

Since the born of the electronic computer, we have used peripherals devices suchas input devices, output devices, storage devices, etc. For many years each company

design their own connector and every device had a different connector. For example, aprinter could use a parallel port, another printer used a serial port and an external tapeunit could use a proprietary system with special adapters. Therefore, connect peripheralswas difficult and expensive. Last part of the 90s saw the development of the USB.

USB: Universal Serial Bus is a standard for connect peripheral devices such asprinters, keyboards, mice, external hard drives, camera, etc. USB eliminate the need ofhave different connectors. You can use the same USB connector for many devices and ifyou need more connectors you can buyhubsfor expand your computer ports.

USB have been the standard since theintroduction of windows 98 with the introductionof the USB 1.0

USB 2.0 is the standard in most PCs now

Besides the Type A, we alsohave the type B, mini-A, mini-B,micro-AB and micro-B

USB connectors

USB is now the standard in connect peripherals from Flash memory tocamcorders.


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Before the developed of the USB, a high-speed serial bus standard was underdevelopment, this serial bus is called Firewall.

Firewall: IEEE-1394, Firewall or i.Link is a high-speed serial standard, thefirewall is not such as popular as the USB but it is faster. IEEE-1394 is used in high-endmusic and video applications.

No all motherboard have Firewall ports, but they canbe installed using an expansion card.

IEEE-1394 connectors

Warning: USB and IEEE-1394 connectors lookdifferent outside the computer but they look the same

inside the motherboard. In fact, a USB connector ina motherboard will fit a Firewall but it will not work.Read the connectors labels before connect USB andFirewall cables to the motherboard.


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In the next pictures, we can see some internal Firewall connectors. In themotherboard, the Firewall connector has the same size of a USB connector but they

always have the letter 1394 whereas the USB connector has the word USB. They alsouse different color. The connectors colors varied in every motherboard.

USB connectors

Firewall connector

USB and IEEE-1394 connectors


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2.2.10Power connectors

In order to work the motherboard needs power. All motherboard have aconnector where you can connect the power supply, this connector has evolved withtime. 15 years ago motherboards used a connector called P8 and P9, really it was twoconnectors in one, then we had the 20 pins ATX connectorand now we have 24 pins ATXconnector.

ATX 20 pins connector

The difference between the 20 and 24 pins is that a motherboard with 24

generally consumes more current. A power supply connector with 20 pins can fix in amotherboard with 24 connectors, but sometimes it cannot provide enough current.Sometimes you can plug the 20 pins power supply to the 24 pins motherboard and theywork perfectly but as soon you plug a new expansion card it can be burned because thepower supply does not support the extra load.

20 Pins power supply connector in a 24 pins motherboard connector


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You can find adapters for connect 20 pins power supply into 24 pins socket, butI do not recommend them because they do not resolve the extra power problem. The use

of adapters can be dangerous because the motherboard will try to get extra power andthis could burn the power supply.

24 Pins power supply connector in a 20 pins motherboard connector

Modern 24 pins power supply can fit in old 20 pins motherboard connectors, there isnot problem if you do this, because modern power supply have more power and havehigher current than old ones.

All the power supply connectors have small keys, with these keys they can only beconnected in one direction. I will teach more about power supply in the chapter dedicateto power supply.


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Besides the main power connector, a motherboard has the following connectors:

ATX12V Connector: This is an auxiliary power connector develop many yearsago, it is a standard in all modern motherboard. This connector power up the

processor

System Fan connector:This is a connector for power up the case fan

CPU Fan connector:This connector controls the processor fan.

Power Jumpers: In this jumper, you connect the cable coming from the chassisfront panel. Generally, it has four pairs of cables; the cables have the followingfunctions.

o Power button

o Reset button

o Power indicator LED

o Hard drive indicator LED.

I took the chassis power button in orderto show the connections.

Motherboard Power Jumpers


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2.2.11 I/O connectors

In this section we will study the motherboard Inputand Outputconnectors, wehave many connectors depending on the motherboard manufacturer In the next picturewe can see the rear part of one typical motherboard.

Motherboard I/O connectors

Some times the motherboards or the computer case have bays, these bays cansupport a great variety of components such as USB ports, Firewall ports, speakers,microphones, etc.

Motherboard external I/O bay

The bay must be connected to the motherboard using a variety of cables. Thesebays can be bought by separate.


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CD Connector

Auxiliary Connector

Audio Connector

Firewall

USB

Inboard motherboard connectors

We have studied the USB and Firewall connectors; now in this section we willstudy the audio connectors. Usually all computers have these audio connectors.

Speaker: In this port, you connect the speaker system. Normally theyconsist in two speakers or two speakers with on subwoofer the last one iscalled a system 2.1. This jack is generally color green.

Microphone: You can connect a microphone to do recorders in the

computer This Jack is generally color pink.

Line in: It is very useful when you try to convert external music to MP#files or when you edit a video content. This Jack is generally color blue.

In systems that are more complex, we can find 5.1 audio out, this jacks let us use5.1 audio equipment. Most 5.1 has audio 3 connectors, one for the front speakers, one forthe rear speakers and the last one for the central speaker and subwoofer.

Besides the audio component we have the video components, most motherboard

uses the VGA video connector, some uses the DVI video connector. We will talk aboutthese connectors in the section 2.10 Video Cards.

Modems and Networks connector are also I/O connectors we will cover them inthe section 4 Networking.


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2.2.12 Keyboard and mouse connectors

Keyboards and mice are the primary input device used in computers. Modernkeyboards and mice use USB connectors. If the device is corded, you must plug the

device to the USB Port, if the device is cordless you plug and adapter to any USB portand the adapter receive signals from the device. In this section, we will study thekeyboards and mice connector in the motherboard.

Keyboard connector: Some years ago, PC used the DINconnector, todayif youbuy a motherboard with Keyboard connector possible it has the PS/2 called also miniDIN.

Mice connector: Since the development of the GUI(Graphic User Interface), micehave become a standard in all computers, first in the Macintosh systems and now inWindows systems. At the beginning mice use the motherboard serial port as connector,later it used the PS/2 connector and now they use the USB port.

The Keyboard and mouse connector look the same, both are PS/2 connector,nevertheless the keyboard connector is purple whereas the mouse connector is green.

Keyboard and mice connectors, USB adapter


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If you have a standard mouse or keyboard, you can buy adapters in order toconnect them to USB ports. You can also buy adapters for connect USB input devices to

standard keyboards or mice ports.

Trackball devices uses the same port that mouse uses, keyboard and mousecombo use the same keyboard port. I will tell you more about keyboards, mice and otherinput device in the section 2.8Input devices.

2.2.13 installing a new motherboard

Although buying a motherboard is one of the most important factors in buildinga PC, the installation itself is very easy. Before continuing, we must understand whysomebody needs to buy a motherboard and the factors to take in consideration. The

reasons to buy a motherboard are:

The motherboard in your system does not work

You need upgrade your computer

You are building a new system.

My experience teaches me that motherboards almost never go wrong. In manycases the motherboard is the last part in be replaced and when it is replaced is because isold and not because it does not work.

In the case you need replace a motherboard because it does not work anymoreyou must know it is almost impossible to find one with the same characteristics andgenerally, you will have the replace the processor too. The problem is motherboards aremade for and specific processor, and processors changes very fast. That means if youhave an old processor it will be almost impossible to find a modern motherboard thatwork with that processor.

Note: If you are installing an old motherboardwith standard keyboard and mouse plugs, generallyyou cannot use UBS devices in the installation. Manykeyboards and mice have drivers you must installafter the operative system is installed.


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You can know if a motherboard works properly using a POST card. If you haveanother computer, you can test the components of the motherboard individually, if allthe components are good the problem is the motherboard or processor. You must notesometimes a motherboard component like the inboard video card fail. In this case, you

do not need change the whole motherboard; you can simply install a new video card. Wewill study motherboard problems and solutions in the section 6.2Hardware problems.

The bottom line is if you have an old system and your motherboard die, it isbetter replace the motherboard and processor all together. If you have problems tryingto buy a motherboard than support your old memory, replace the memory as well.

Cheap motherboards can cost less than $100, but if at the same time you arereplacing the processor and memory, the expenses will be more. If you are building anew system, it is possible you do not need to look for a motherboard that work with oldparts, this give you a big array from where to choose.

In order to remove your old motherboard, you must follow the nextsteps:

Unplug the power cable in the computer.

Open the case.

Discharge your static and hold the motherboard by its sides, do nottouch any electronic components.

Unplug the power supply, hard drives and optical drives cables.

Unlock and pull the memory modules.

Unplug all the expansions cards.

Unlock and pull the processor fan.

Unlock and pull the processor.

Unscrew the screws that hold the motherboard to the computer case.Keep the old screws as well as any spacers and washers.

In order to install a new motherboard the installation is reversal to the removal.

Note: Sometimes you had an old video card and now you are using the in-boardvideo card from your new motherboard. In this case, you must find an expansion cardcover; otherwise, dust will enter inside your computer.


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If you are reusing your same processor, you will need to put a little bit of thermalcompound between the top of processor and the bottom of the heatsink. Newprocessor comes with a little bit of thermal compound, but you can buy it in anycomputers supply store, we will talk more about this in 2.3 Microprocessors.

Some cooling systems have different heatsink bases if this is the case you mustchange the heatsink base before you attach the motherboard to the case. I will teach youmore about heatsinks in the section 2.3 Microprocessors.

The back of the motherboard must nevertouch the case. In order to avoid thisproblem you must put spacersbetween themotherboard and case.

If you install expansioncards, you must take offthe expansion cardcovers.

Installing a motherboard

In the case of notebooks, the motherboards are very expensive. If themotherboard inside your laptop does not work properly, you will have to buy one exactlythe same, you cannot upgrade it with a better motherboard model. You will have to buy itfrom the manufacturer and the production of new motherboard can last only a pair ofyears. Therefore, you cannot buy a new laptop motherboard for old models. If you haveand old notebook and you need replace your motherboard I recommend buy a newnotebook instead.


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2.3 Microprocessors

2.3.1 Processors History The 17th and 18th centuries marked the beginning of the modern mechanical

computers. In the 19th century Charles Babbage drafted the blueprint of the AnalyticalMachine, this machine would have been the first programmable but it was never finished.This computer could be programmed using punched cards similarly to the card used bycomputer 150 years later.Ada Lovelacedid the programming for this machine, she was anextraordinary mathematician and considered the first programmer.

Part of Babbage differenceengine, circa early 19th century.

Part of a 19th century computer

Mechanical computer continued been developed until the middle of the 20century, which mark the beginning of the electronic computer. John Von Neumannisconsidered the father of the modern computer architecture.

This Computer used Vacuumtubes in its design, circa 1951

EDVAC Computer

Most computers today use Von Neumann architecture. One key concept inmodern computer is the development of the CPU.


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The CPUor Central Processing Unitis the computer brain. The CPU performs thecalculation and processing. In order to do this processing, it has to follow the instructionwritten in the computer program.

In the 40s early CPU were designed specifically for a single computer, they usedvacuum tubes and electrical relays, transistor were used in the 60s and Integrate circuitsor IC in the 70s.

This computer used

ICs in its design,circa 1965.

CPU, memory and external bus interface of a DEC PD-8/l

In the 70s the processor or microprocessor was introduced. The developed of

the processor changed dramatically the advance of the PC. The importance of theprocessor is that all the CPU architecture in now embedded in the processor. The processor becamethe CPU.

Intel 4004, the first processor early 70s


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Intel 80486DX2 early 90s

AMD (Advance Micro Devices) and Intel (Intel Corporation) are the two biggestmanufactures of processors. The development of the processor has been very fast. The8086 from 1978 had 29,000 transistor, the 486 from 1989 was had 1.2 milliontransistors, right now the processors manufacturers companies are working in the firsts 1billion transistor processor.

Before continuing study the processor there are some concepts we need tounderstand.

Math Coprocessor.

Clock Speed

Data I/O bus

Internal registers

Address bus

Cache memory

Parallelism

Processor sockets


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2.3.2 Math Coprocessor

One important part of the processor is to carry floating-point arithmeticoperations, these operations are used for resolve complex mathematical problem such as

CAD (Computer Aided Design) software, video games, video modeling, scientificresearch and engineering calculations. One way to give the processor more computingpower was add a math coprocessor.

A math coprocessoris a special processor used to help the main processor with thecomplex mathematical functions. Many old systems prior to the 486 processor had a slotwhere you can add a coprocessor. Since the 486 processor all the math coprocessor isembedded inside the processor. Today if you need more processor power the favoriteway to get it is using multiprocessing or video card with dedicate Graphic Processing UnitsorGPUs.

2.3.3 Clock Speed

A computer execute instructions following a determinate program, theseinstructions are a series of step that the computer must follow. The processor executethese steps triggered by a clock signal, the clock speed is the frequency in which theprocessor execute these instructions. The processor clock rate or speed is measured inmillions of cycles per second or megahertz (MHz).

You must take in consideration that no all the processor have the same speed,therefore in order to execute a instruction the processor may need many clock cycles, for

example the processor 8086 needs an average of 12 cycles to execute an instructionwhereas the processor Celeron can execute three or more instruction per cycle.

Therefore, you cannot compare a Pentium 4 running a 1000 MHz with a Atlonrunning also a 1000 Mhz. Compare the velocity of different processor is difficult.

The processor speed must always match the motherboard speed, some years agoyou needed set some jumper in the motherboard in order to set the right speed, now inmodern processor you can set the speed via software. Sometimes this software is alsoused for overclocking.


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Overclocking: If you need a faster system, the best way to do it is buying a newprocessor. However, since buying a new processor is expensive; many computerenthusiasts use a technique call over clocking. Over clocking a processor means running theprocessor at a higher clock rate.

When you over clock a processor you have the advantage of gain more speed butyou have some disadvantages as well; the processor becomes hot, the computer canbecome instable and sometimes this instability is difficult to diagnose.

If you decide use an over clock system, you can over clock the processor byyourself or buy an already over clocked system from a retailer. Nowadays you can overclock a processor using software, the uses of software let control the processor speed andmeasure the processor temperature.

2.3.4 Data I/O bus

The data bus is used to send and receive data, the processor has internal data busand external data bus, before continuing learning about data you must understand themeaning of bit

The data inside a computer is stored in bits, a bit is a unit of informationa bit hastwo distinct states On and Off, generally these states can be represented by voltage,light intensity or magnetization. For example a voltage of 5 volt could represent the stateof onwhereas avoltage of 0 volt could represent the state of off. A bit can be Onor Off. If you want to know more about bits you can get more information reading theappendix.

The external data bus is composed by a series of pins or wires. These pins used

to send and receive data. The data bus width indicates how much data it can handle. Forexample a bus with 16 wires can handle 16 bits, the data bus can be of 4, 8, 16, 32 or 64bits depending of the processor.

The external and internal bus could have different width. Generally when thepeople talk about the data busthey are really talking about the external data bus.

Warning: Over clocking a system could inmany cases void the manufacture warranty.


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2.3.5 Internal registers

The internal data bus is made of registers. A register is a series of cells where data arestored. For example if you want add two numbers, you will use three register in the first

register you stored the firs number, in the second register you stored the second numberand in the third register you stored the result. All the information inside a computer isstored in binary.

Binary is a numerical system, this system uses only two values 0 and 1, thereforeall the information like letters and numbers must be translate in binary, for example thenumber 2 in one computer will be translate as 10 and the number 3 like 11. You can readmore about numerical system in the appendix.

The size of the register varied in each processor, in a 16 bits processor theregisters have 16 bits and in a 32 bits processor the register have 32 bits. Therefore, aprocessor could be a 16 bits processor, a 32 bits processor, etc. Most processors now are64 bits.

Examples of 32 bits processor are Celeron, Pentium 4, Pentium 4 Xeon, Duronand Atlon. Examples of 64 bits processor are Intel core i7, core 2 duo, Core 2 quad,Athlon 64 X2 and Phenom ll.

In order to use the full potential that a 64bits processors offer you must use a 64bits operative system such as windows XP 64 bits, windows Vista 64 bits or windows 764 bits.

2.3.6 Address bus

In order to access the data the processor must know where the data is stored. The address bus carries the information representing the location of the memory cellwhere the data is stored. In the next table, you will see a representation of a 2 bits addressbus.

4 bits Address bus

Address Data

00 1001

01 1110

10 1101

11 0001


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In the previous table, we saw a representation of a 2 bits address bus, the addresshas four possible values from 00 to 11, the address 00 has the data 1001, and the address10 has the data 1101. In this example, the address bus has 2 bits and the internal bus has 4bits, if you want read all the information at once, you will need a 4 bits external bus with a

4 bits processor.

You can note that all the information is stored in binary for example the data0001 in binary represent the number 1; the data 1001 represent the number 9. Eachnumber, character or letter has its representation in binary. This is the way computers usefor stored information.

2.3.7 Cache memory

Generally the processor speed is faster than the memory speed, therefore in orderto keep up with the speed, the processor uses the cache memory. The cache memory is a high-speed memory buffer which temporary stored data.

There are generally two types of cache level 1 and level 2.

Level 1 cache memory holds the data that is more probably to be used.Sometimes the data stored in cache 1 is not the date the processor needs.

Level 2 cache is used in the case the level 1 cache fails.

2.3.8 Processor sockets

We already know the motherboard uses sockets in order to connect the

processors in the motherboard. Now we will study the sockets in detail.

Each family of processors uses a distinct type of socket. We have different typesof sockets like socket 1, socket 2, socket 3, etc. Others sockets receive the name of slotslike slot 1 and slot 2, super socket 7, slot A, Slot B, socket AM2+, Socket AM3, SocketLS, etc.

Warning:Never confuse Socket 1 with slot1 or socket 2 with slot 2; the names are

similar but there are different.


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Since the type of sockets determines the processor type and the processorevolves very fast, they become obsolete very fast. Therefore, in any moment you canonly find a bunch of socket families for a bunch of processors. In this moment, we canfind the following processors families:

AMD: AMD Phenom and AMD Atlon.

Intel: INTEL Xeon, INTEL Core, INTEL Dual Core, INTEL Core i5and Intel Core i7.

The socket determines also the velocity the processor can run. For example, themotherboard Biostar 945GC-M with Socket 478 can run Processor Intel Core 2 Duo,Pentium 4 and Celeron up to 800/533 MHZ FSB System Bus; the motherboardGygabyte G41M-ES2L with socket 775 can run a processor Intel Core 2 Duo and IntelCore 2 Quad up to 1333/1066/800 MHZ FSB System Bus.

Therefore, if you want a system with a processor Intel Core 2 Duo, you can useany of the two motherboards but the second one is a lot faster. One motherboard canaccept different types of processors. However, one processor is made for a specific kindof Socket. For example, a processor Core 2 for socket 478 is different from a processorCore 2 for socket 775.

The socket 775 is the replace of thesocket 478, the 775 socket has not holesinstead it has pins.

Processors for socket 775 have contactspoints instead of Pins.

Socket 775


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The motherboard and the processor generally remain together. It is commonupgrade the memory and the hard drive but almost nobody upgrade the processor, thisis because the processor technology change very quickly and the motherboardtechnology has to keep the pace; Therefore if you buy a computer today and you want

upgrade the processor three years later, is almost sure you will need upgrade themotherboard also. For this reason a lot of motherboards are sold in bundle with theprocessor, this is often a very good deal.

Zero insertion Force: This is the design used in all modern processors. Withthis deign you lift a handle in the socket; you set the processor and lock it dropping thehandle. You must align the processor with the socket using the indicator in themotherboard and the notch in the processor.

Indicator key

Handle

Zero insertion force system


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2.3.9 Heatsinks and processors fans

We cannot talk about processors without talk about heatsinks and processor fans.Since the processors have million of transistors, one physical phenomenon is the heat

inside the processor. In order to dissipate the heat, all modern processor use one heatsinkand one fan. The heatsink is a metallic component that you install above the processor inorder to dissipate the heat and avoid the processor overheating, above the heatsink youmust also install a fan.

There are many types of heatsinks and fans. High-end heatsinks use liquid coolerin order to dissipate the heat, modern fan uses software in order to control the fan spinand processor temperature.

Fan

Heatsink

Fan power Cable

The processor isunder the heatsink

Integrated processor heatsink and fanunit

Heatsinks and processors fans


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Fan bottom view

Fan side view You must apply the thermal compound here

Heatsink Thermal compound

Heatsink bases for different socket

High end heatsink and processors fan


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A thermal compound must be applied between the heatsink ant the fan. Oneimportant note is that generally you can buy heatsinks and fans together in a package.New processors sometimes are sold with their own cooling system.

The cooling system attaches to the base, this base is around the processorsocket, and these bases have different size. The size and shape of the base depend of theprocessor socket for example a cooling system for a socket AM2 is different to a coolingsystem for socket 775.High end system are sold with interchangeable bases, in this wayyou can use the same cooling system in many motherboards. If you are upgrading yourmotherboard and want to use your old cooling system sometimes you will need changethe heatsink base first.

The fan is attaching to

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