PC HARDWARE SERVICING - Weeblypchssepnaskto12.weebly.com/uploads/2/2/8/6/22868856/module_0... · PC HARDWARE SERVICING ... Hand Tools. ... 1.1 Hardware: The mechanical and electronic

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PC HARDWARE SERVICING The Strengthened Technical-Vocational Education Program

How to Use this Module .......................................................................................................... i 1 Introduction ............................................................................................................................ ii Pre-Test .................................................................................................................................. iii

Definition of Terms ................................................................................................................ iv

Learning Outcome 1: Introduce the Computer System ..........................................................7 Information Sheet 1.1:Types of Computer ..........................................................................8 Self Check 1.1 .................................................................................................................... 11 Information Sheet 1.2: Computer Components and its Characteristics ........................... 12 Activity Sheet 1.2 ...............................................................................................................16 Self Check 1.2 .................................................................................................................... 17 Information Sheet 1.2: Distinguishing Hardware and Software Relationship ..........................................................................................................................18 Activity 1.3 ......................................................................................................................... 19 Learning Outcome 2: Identify of computer parts and its peripherals ................................ 20 Information Sheet 2.1: Personal Protective Equipment ................................................... 21 Self Check 2.1 .................................................................................................................... 25 Information Sheet 2.2: Hand Tools. .................................................................................. 26 Activity Sheet 2.2............................................................................................................... 28 Information Sheet 2.3 ....................................................................................................... 30 Activity Sheet 2.3............................................................................................................... 58

Self Check 2.3 .................................................................................................................... 59

Learning Outcome 3: Maintain Computer Hardware .......................................................... 61 Information Sheet 3.1: Maintain computer System ......................................................... 63

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Information Sheet 3.2: Cleaning Your Computer System ................................................. 66 Activity Sheet 3.2............................................................................................................... 69 Information Sheet 3.1 ..................................................................................................... 70 Post Test ............................................................................................................................... 71 Answer Keys ......................................................................................................................... 72

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Welcome to the Module “Introducing Computer System”. This module contains training materials and activities for you to work on. The unit of competency “Introduce Computer System” contains knowledge, skills and attitudes required for a Computer Hardware Servicing NC II course. You are required to go through a series of learning activities in order to complete each of the learning outcomes of the module. In each learning outcome there are Information Sheets and Activity Sheets. Follow these activities on your own and answer the Self-Check at the end of each learning activity. If you have questions, don’t hesitate to ask your teacher for assistance.

After completing this module ask your teacher to assess your competency. Result of your assessment will be recorded in your competency profile. All the learning activities are designed for you to complete at your own pace.

Inside this module you will find the activities for you to complete followed by

relevant information sheets for each learning outcome. Each learning outcome may have more than one learning activity.

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Program/ Course : Computer Hardware Servicing NC II Unit of Competency : Introduce Computer System Module Title : Introducing Computer System INTRODUCTION: This module contains information and suggested learning activities on Computer Hardware Servicing. It includes training materials and activities for you to complete. Completion of this module will help you better understand the succeeding module on Computer Hardware Servicing. This module consists of 3 learning outcomes. Each learning outcome contains learning activities supported by each instruction sheets. Before you perform the instructions read the information sheets and answer the self-check and activities provided to ascertain to yourself and your teacher that you have acquired the knowledge necessary to perform the skill portion of the particular learning outcome. Upon completion of this module, report to your teacher for assessment to check your achievement of knowledge and skills requirement of this module. If you pass the assessment, you will be given a certificate of completion. SUMMARY OF LEARNING OUTCOMES: Upon completion of the module you should be able to: LO1. introduce the computer system LO2. identify the computer parts and their peripherals LO3. maintain computer system

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Multiple-choice:

1. What do you call the large screen in a laptop? a) CPU b) Mother board c) Video Card d) LCD 2. What type of motherboard design that is common in large PC network

servers and on other computers on which the processor is upgraded frequently?

a) Motherboard b) CPU c) Backplanes d) ATX 3. It serves as the power supply for your laptop? a) AT b)Power Supply c) CMOS d) Battery 4. It defines a motherboard’s size, shape and how it is mounted to the case? a) Motherboard b) Form factor c) LGX d) PSU 5. It is also known as mainboard, system board or planar? a) Motherboard b) Motherboard Style c) CPU d) LXG

6. It is the skeletal frame work of your computer system. a) Cover b) Chassis c) Screws d) Power supply 7. It provides protection for the internal parts of the computer. a) Chassis b) Reset c) Case d) Cover 8. The part of the computer that provides power to the entire system? a) CPU b) Drive Bay c) Power Supply d) Reset 9. A button that allows the user to Turn off the computer. a) Reset b) Turbo c) LED d) Power switch 10. The part of the chassis where you place the Motherboard drives. a) Drive Bay b) Cover c) Chassis d) CPU

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Form factor - The industry standard that defines the physical and external dimensions of a

particular device. AT - Advance Technology ATX - (Advance Technology Extended) is a computer form factor designed by Intel in

1995. NLX - (New Low Profile Extended) was a form factor proposed by Intel and

developed jointly with IBM, DEC, and other vendors. Watts - is the SI derived unit of power, equal to one joule of energy per second. Ergonomic - The study of work organization, and the human/machine interface in

particular. Sensor - The study of work organization, and the human/machine interface in

particular. Platter - The actual storage media in the different type of disk. In the hard drive the

platter have a core of glass or aluminum, covered with a thin layer of Ferric oxide or Cobalt alloy (Co-Ni, Co-Cr, Co-Ni-W).

Magnetic - having the properties of a magnet; i.e. of attracting iron or steel; "the hard

disk is covered with a thin coat of magnetic material". Static electricity- refers to the buildup of electric charge on the surface of objects.

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Program/ Course : Computer Hardware Servicing NC II Unit of Competency : Introduce the Computer System Module Title : Introducing the Computer System

Learning Outcome 1 : Introduce the Computer System ASSESSMENT CRITERIA:

1. Types of computers according to size and use are identified. 2. Characteristics of hardware, software and firmware are identified. 3. Relationship of hardware and software in a computer system are distinguished.

RESOURCES:

Equipment and Accessories Tools Materials LAN Card UPS 24 port-Hub Modem Computer Unit USB External CD writer USB Scanner USB Printers USB Flash Drive

Screwdriver(standard) Screwdriver(Philips) Long nose pliers Mechanical pliers Allen wrench Multi-tester Crimping tools Wire Stripper LAN Tester Anti-static wrist wrap Device drivers/installers

Software Applications RJ 45 UTP Cat 5 cable Motherboard’s Manual and Installer Sound Device Driver Installer

REFERENCES:

Antoinette R. Marcelo. Understanding PC Hardware. Copyright 2007 Jemma Inc.

McLaughlin,Robert, Sasser,Susan, Ralston,Mary.Fix Your Own PC.Philippine Graphic Arts, Inc Tandang Sora St.Caloocan City

Meralco Faoundation. Microcomputer Servicing Plus. Pasig City, Philippines.

Legaspi,Carlos, Caiña, Mark Anthony. Operate A Personal Computer. Dasmariñas Computer Learning Center.Dasmariñas,Cavite, Philippines

Bigelow,Stephen J. PC Technician’s Troubleshooting ,McGaw Hill

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INFORMATION SHEET 1.1

TYPES OF COMPUTER

What are computers?

Computers are electronic devices that are capable of processing data/information given in the form of numbers, words, pictures, and even sounds.

They can be programmed (given instructions) to carry out various kinds of information processing jobs.

Different Kinds of Computers

Depending on the size and capacity, computers are classified into three types:

MAINFRAME COMPUTERS

MINICOMPUTERS

MICROCOMPUTERS OR PERSONAL COMPUTERS. Mainframe Computers

Large and powerful computers that are used by many people (users) at the same time; typically installed in large organizations/companies.

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Supercomputers

Extremely powerful mainframe computers used in scientific and engineering applications.

Minicomputers

• Minicomputers are medium sized computers -- Between Mainframe computers and Microcomputers

Application of Computers

Various kinds of jobs that are done using computers:

SCIENTIFIC COMPUTATIONS

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KEEPING TRACK OF INFORMATION

Example:

Banking, Railways or Airlines Reservations

PREPARATION OF DOCUMENTS AND MULTIMEDIA PRESENTATIONS Examples: Power point Presentations in meetings and seminars. Video presentation of films and footages

SIMULATION OF REAL OR IMAGINARY WORLD SCENES Example: Virtual Reality, Computer Games

STORING AND SHARING INFORMATION Example: World Wide Web(Internet) Web Casting

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Matching Type: Directions: Match column A to column B. Place your answer in the answer sheet given by your teacher. A B 1. Personal Computer V- 2. Mainframe Computer W- 3 Mini computer X- 4. World Wide Web Y- 5. Super Computer Z-

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Computer components and its characteristics

Components of a Computer

1. The components of a computer are classified into the three main categories hardware, software and documentation. 1.1 Hardware: The mechanical and electronic parts that perform the various tasks of the computer 1.2 Software: The programs or instructions that tell the hardware what tasks are to be done and how. 1.3 Firmware/Documentation: Instructions in read only memory (ROM).

1.1 Hardware components The hardware of a typical computer system, irrespective of its size, consists of the following components: 1.1.1 CENTRAL PROCESSING UNIT – CPU

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1.1.2 MEMORY

.

1.1.2 STORAGE DEVICES

1.1.4 INPUT / OUTPUT DEVICES

1.2 Computer Software

1.2.1 Computer Software/Program

A software/program is a sequence of commands written in a computer programming language that specifies a task that the computer will perform.

Some of the computer programming languages are: VISUAL BASIC, C, C++, JAVA

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Classification of Computer Software

Computer software can be classified into following categories: OPERATING SYSTEM USER PROGRAMS APPLICATION PROGRAMS

Operating System

• Operating system (OS) is the basic software responsible for interacting with the hardware.

• It is the foundation on which user programs and application programs are built. • It helps the user to enter programs or data, store them in files and execute

programs. • Two popular operating systems in use today are

Unix – for mainframes and minicomputers. Windows and Linux – used for personal computers.

User Programs • User Programs: Written by users or programmers for themselves or for their

organization.

Application Programs • Computers are increasingly being used in almost every activity - business,

industry, commerce, health, education, entertainment, sports, etc.

Word processing

Desktop Publishing

Spreadsheets

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Ms Word MS Excel MS Powerpoint

1.3 Firmware

Is the program that is embedded in a silicon chip rather than stored on a floppy disk.

You can access the computer BIOS utility by pressing a special key right after you turn on your computer. The special keys are (DEL) delete key or (F2) Function key no.2 or (F10) function key no. 10

Example: BIOS chip or CMOS

CMOS CHIP

BIOS UTILITY

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Equipment, Tools, and Materials Personal Computer Directions:

1. Choose a partner to work with. 2. Given the following equipment, ask your partner to identify the functions and

characteristics of the computer components (hardware/software/firmware) of a computer unit. (Give at least 2 for each component)

3. Exchange roles. Your partner will now do the identification, functions and characteristics.

4. Assess each others performance using the performance criteria score card below.

PERFORMANCE SCORE CARD

Performance Criteria Scoring

1 2 3 4 5

1. The hardware functions are identified successfully.

2. The software and firmware function is identified successfully.

3. Proper access to the firmware is carefully observed.

4. Safety precautions are observed.

5 - Excellently Performed 4 - Very Satisfactorily Performed 3 - Satisfactorily Performed 2 - Fairly Performed 1 - Poorly Performed

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Multiple choice:

1. What do you call a program embedded on a silicon chip? a) Peopleware b) Software c) Firmware d) Hardware 2. What do you call the software that interacts with the computer hardware? a) Applications b) Operating System c) Firmware d) Spreadsheets 3. The mechanical and electrical part of the computer system is the. a) Software b) Hardware c) Unix d) Firmware 4. An operating system used in mainframes and mini-computers is the. a)Windows XP b) Unix c) Panda d) BIOS 5. Which one is an example of an operating system commonly installed in

personal computers. a) Unix b) Windows c) BIOS d) MS-Word

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Software

INFORMATION SHEET 1.3 Distinguishing Hardware and Software Relationship Hardware and Software Relationship For a computer to produce useful output its hardware and software must work together. Nothing useful can be done with the hardware on its own, and software cannot be utilized without supporting hardware.

To take an analogy, a CD player and its CD purchased from the market are hardware. However, the songs recorded on the CD are its software. To listen to a song, that song has to be recorded on one of the CD first, which is then mounted on the compact disk and played. Similarly, to get a job done by a computer, the corresponding software has to be loaded in the hardware first and then executed.

Following important points regarding the relationship between hardware and software are brought out by this analogy:

1. Both hardware and software are necessary for a computer to do useful job. Both are complementary to each other.

2. Same hardware can be loaded with different software to make a computer perform different types of jobs just as different songs can be played using the same CD player.

3. Except for upgrades (like increasing main memory and hard disk capacities, or adding speakers, modems, etc.); hardware is normally a one- time expense, whereas software is a continuing expense. Like we buy new cassettes for newly released songs or for songs whose cassettes, we do not have, we buy, new software to be run on the same hardware as and when need arises, or funds become available.

The computer is useless without your Software

Your software is useless without your Hardware

Hardware

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Interview Directions:

1. Work in groups of 6 as a panel. One will be the interviewer ,while the rest of the panel will answer

2. The students will be asked the following questions. o Why do computers need software? o Why do we need to install different software in our computers? o Briefly explain the relationship between computer hardware and software. 3. Rate your groups’ performance using the Performance score card below:



1 2 3 4 5

1. Importance of computers is clearly explained.

2. Installation of different software is explained.

3. Relationship between hardware and software is well explained.


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Program/ Course : Computer Hardware Servicing NC II Unit of Competency : Introduce Computer System Module Title : Introducing Computer System

Learning Outcome 2 : Identify of computer parts and its peripherals ASSESSMENT CRITERIA:

1. Appropriate personal protective equipment used in Hardware Servicing is identified.

2. Appropriate tools are used according to standard safety procedure. 3. Identification of the different computer parts is identified. 4. Characteristics and functions of each computer component are identified. 5. Safety precautions are observed at all times.

REFERENCES:

http://en.wikipedia.org/wiki/Customer_service

http://en.wikipedia.org/wiki/Quality_standard

http://www.technet.unsw.edu.au/tohss/swp.htm

http://xnet.rrc.mb.ca/healthsafety/safeworkprocedures


http://www.empf.org/empfasis/aug04/prop.htm

http://www.lakeland.cc.il.us/~internal/policymanual/10fiscalaffairs/1026.POL.htm




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Personal Protective Equipment

Refers to protective clothing, helmets, goggles, or other garment designed to protect the wearer's body from injury by blunt impacts, electrical hazards, heat, chemicals, and

infection, for job-related purposes. Personal Protective Equipment used in Hardware Servicing There are certain personal protective devices used in computer hardware servicing, this equipments are designed to protect the devices against ESD ( Electro Static Electricity) and other environmental hazards.

Anti- Static Devices

Devices used to protect the computer unit against static electricity.

.1 Anti- Static Wrist Strap

.2 Anti-Static Mat

http://en.wikipedia.org/wiki/Clothing

http://en.wikipedia.org/wiki/Helmets

http://en.wikipedia.org/wiki/Goggles

http://en.wikipedia.org/wiki/Injury

http://en.wikipedia.org/wiki/Chemicals

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.3 Anti Static Spray - Use to remove ESD from your work area

1.4 Anti- Static Bag

-Use to store your sensitive devices safe from ESD.

2. Power Protection Devices

- Devices use to protect the user and the computer from sudden increase/dropped of electricity. Power protection devices are also used against sort circuits.

2.1 AVR (Automatic Voltage Regulator) -Automatically maintain a constant voltage level.

http://en.wikipedia.org/wiki/Voltage

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2.2 UPS (Uninterruptible Power Supply)

- Serves as a battery backup, provides emergency power

2.3 Surge Suppressors - An appliance designed to protect electrical devices from voltage spikes.

Personal Protective Equipment application Anti-static devices - Always use an anti-static wrist strap when working on a computer except when working on monitors: more about that below. One end is an elastic band that fits around your wrist and which is connected to an alligator clip by a wire. The clip connects to a metal part of the computer chassis, which equalizes the voltage between you and the computer, thus avoiding static sparks.

http://en.wikipedia.org/wiki/Electricity

http://en.wikipedia.org/wiki/Voltage_spike

http://www.kitchentablecomputers.com/static.htm#monitors

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Power Protection Devices

- Plug the computer to protection device to avoid voltage spikes and power surges.

UPS

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Identification Type Directions: Answer the following questions and place your answer on your test booklet.

1. A device used against power/voltage spikes. 2. A power protective equipment that serves as a backup battery for your computer. 3. It is used to store sensitive computer peripherals. 4. A anti-static device you need to use when touching components in a computer unit. 5. A device that provides a stable power system.

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Using Hand Tools Hand Tools

- device for performing work on a material or a physical system using only hands. The hand tools can be manually used employing mechanical force, or electrically powered, using electrical current.

Types of hand tools

Side Cutter Pliers – a tool used for cutting or trimming of connecting

wires or terminal leads in the circuit board

Long nose Pliers – Used for holding, bending and stretching the lead of

electronics component or connecting wire.

Crimping Tool- a tool use to connect a RJ45 connector to a network

cable.

Tweezers- a tool use to hold small sensitive part of a computer.

Cutter- a tool used in cutting wires.

Flat Screw Driver – a tool used to drive or fasten negative slotted

screws

Philips Screw Driver- a tool used to drive or fasten positive

slotted screws

http://en.wikipedia.org/wiki/Material

http://en.wikipedia.org/wiki/Hand

http://en.wikipedia.org/w/index.php?title=Mechanical_force&action=edit&redlink=1

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Flashlight- a small electric light, use to illuminate a dark area..

Paint Brush - use for cleaning parts of a computer.

Magnifying glass- a device made in glass with handle, to exaggerate

or to increase the apparent size of an object.

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Equipment, Tools, and Materials Basic hand tools Directions: 1. Choose a partner to work with. 2. Given the following equipment you are asked to identify the hand tools and functions. 3. Take turns in during the task.

4. Assess each other using the criteria in the score card below.



1 2 3 4 5

1. All hand tools are identified successfully.

2. All functions are identified successfully.

3. Proper handling of tools is observed.

4. Safety precautions are observed.


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Matching Type: Directions: Match column A to column B, place your answer in the answer sheet given by your teacher. A B 1. Phillip Screw driver H-

2. Crimping Tool I- 3 Flash Light J - 4. Tweezer K- 5. Magnifying glass L-

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Hardware Components and Peripheral Your PC’s system case is probably high on the list of components you think about the least. However, in spite of the fact that the system case has only one or two components that are active, namely the power supply and the front panel, the PC’s case plays a major role in the PC’s operation. In spite of the fact that the PC’s case just seems to sit there, it does perform a number of very valuable functions.

Provides the aesthetics of the system

Provides the PC with its structure

Provides protection and cooling for the electronics and other devices mounted inside

Computer case comes in al sizes, shapes, colors and faces. These variations in size

and shape are driven by the case’s form factor. The form factor of the case is its shape, the way its components fit together and most of all its size.

Chassis the skeletal framework that provides the structure, rigidity and strength of the case.

Cover plays an important role in the cooling, protection and structure of the PC.

Power Supply a very important component, not only to the case assembly, but to the PC and its other components.

Front panel in addition to providing the PC with its looks and color, the front panel also provides information on the PC’s status, allows the user to physically secure the PC and on some case types, it is the starting point for removing the case cover.

Power switch

Reset switch

Status LED

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Power LED (Light Emitting Diode) typically green in color and illuminated when the PC’s power is on.

Hard drive LED when the drive is seeking, reading or writing data, this red, orange or amber LED is lit and flashes.

Turbo LED if present, this yellow LED indicates that the PC is in turbo mode.

Switches most new systems now have their two main switches, the power switch and the reset switch, on the front panel.

Power button - in older PCs, the power switch was a part of the power supply and located on the right rear corner of the PC.

Reset button performs a hardware reset when pressed. This provides the user with a means of restarting the PC should it halt and not respond to normal shutdown or restart command.

Drive bays disk drives with removable media have been mounted in the system case so that they can be accessed from the front panel. Typically, the drive bays are used for 3.5-inch disk drives, optical drives and removable hard drives.

External drive bays these drive bays are actually internal to the case and chassis, but they can be accessed externally.

Internal drive bays these drive bays are completely inside the system case and are not accessible from outside the chassis

System Case Styles 1. Desktop case – the flat, boxy one is the desktop case PC. It doubles as the

base for PC’s monitor. 2. Tower cases – the tall, thin case are the tower style. Below are the

popular variations of the tower case

Full tower are the largest standard PC cases available. They offer the most of any case style in the way of expandability, typically having three to five external drive bays and a few internal drive bays as well.

Cover

Switches

Drive Bays

Front Panel

Power Supply

Chassis

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Mid-tower is a slightly shorter version of the full tower.

Midi-tower exist somewhere between the mid-tower and the mini-tower. By definition, a midi-tower is smaller than a mid-tower and larger than a mini-tower.

Mini-tower this is the most popular case today. It provides slightly more expansion capacity than desktop cases.

Desktop Case

Tower Case The Power Supply The power supply unit (PSU) in a computer regulates and delivers the power to the components in the case.

Power Supplies contain dangerous voltages and should only be opened by experienced and qualified engineers; there are no user serviceable parts inside. Always disconnect the PSU from the mains supply before removing the cover of the PC.

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Standard power supplies turn the incoming 110V or 220V AC (Alternating Current) into various DC (Direct Current) voltages suitable for powering the computer's components. Power supplies are quoted as having a certain power output specified in Watts, a standard power supply would typically be able to deliver around 350 Watts. The more components (hard drives, CD/DVD drives, tape drives, ventilation fans, etc) you have in your PC the greater the power required from the power supply.

By using a PSU that delivers more power than required means it won't be running at full capacity, which can prolong life by reducing heat damage to the PSU internal components during long periods of use. Always replace a power supply with an equivalent or superior power output (Wattage). There are 3 types of power supply in common use:

AT Power Supply - still in use in older PCs.

ATX Power Supply - commonly in use today.

ATX-2 Power Supply - recently new standard.

A power supply can be easily changed and are generally not expensive, so if one fails (which is far from uncommon) then replacement is usually the most economic solution.

The power supply connectors

4 Pin Berg Connector -Used to connect the PSU to small form factor devices, such as 3.5" floppy drives. -available in: AT, ATX & ATX-2

4 Pin Molex Connector -This is used to power various components, including hard drives and optical drives. -available in: AT, ATX & ATX-2

20 Pin Molex ATX Power Connector -This is used to power the motherboard in ATX systems. -available in: ATX( ATX-2 have four extra pins)

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4 Pin Molex Power Connector -Used specifically for Pentium 4 Processor Motherboards. -available in: ATX (integrated into the power connector in ATX-2)

6 Pin AUX Connector -Provides +5V DC, and two connections of +3.3V. -available in: ATX/ATX-2

ATX Power Supply Pin outs Below are pin out diagrams of the common connectors in ATX power supplies.

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The Motherboard

The motherboard is easily the most important part of the computer. Although there are a number of components that a PC cannot function without, it’s the motherboard that ties them all together and turns them into a personal computer.

The motherboard, or main board, of a PC is a large printed circuit board that is home to many of the most essential parts of the computer, including the CPU, chipset, cache, memory sockets, expansion bus, parallel and serial ports, mouse and keyboard connectors and IDE, EIDE or SCSI controllers. Thee motherboard binds the PC’s operational components together. Motherboard Form Factors Form factors define a motherboard’s size, shape and how it is mounted to the case. However, form factors now include the size, shape and function of the system case; the type, placement and size of the power supply; the system’s power requirements; the location and type of the external connectors, and the case’s airflow and cooling system.

AT(Advance Technology) Form Factor The initial design of motherboards introduced by IBM (International Business Machines)

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ATX Form Factor It was released by Intel in 1995 and was an improvement over the LPX form factor. Mini ATX This is slightly smaller than ATX but all the specifications of the ATX are included. NLX Form Factor A new standardized form factor. The three primary focuses of the NLX are the processor and system cooling, the number of connections for multimedia hardware and reducing the clutter of interior cables.

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The Components of the Motherboard The motherboard is composed of the following parts:

The Central Processing Unit

CPU stands for Central Processing Unit. It is the brain of the computer unit.

The reason the CPU is called a processor is because it can work with data. And it has two important jobs:

It can do calculations.

It can move data.

The CPU is very fast at doing both jobs. The faster the CPU can do calculations and move data, the faster we say the PC is. What follows is a short description of how to achieve faster data processing. Read it, and see if you understand all the concepts. There are three ways to improve a PC’s performance.

CPU

Back panel

Memory Slots

Expansion slots

CMOS

Power Conner

stor

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The Evolution of the CPU Intel CPU Family Tree

1. First Generation: 8088, 8086, 80188, 80186and 8087 – these were introduced in 1978 and had a clock speed of 4.77MHz. .

Intel 8088 2. Second Generation: 80286 and 80287 – it has a clock speed of 6 to 8 MHZ and uses

16 bit data bus.

80286 CPU

3. Third Generation: – this was a full 32 bit processor and has clock speed of 16 MHz.

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4. The Fourth Generation:– this CPU incorporates a cache memory and an integrated math coprocessors. This was the first to use Intel’s new socket numbering system, the Socket 1.

486DX and Socket 1

5. The Fifth Generation: Intel “P5” Pentium and Pentium MMX “5” was originally known as 80586, but Intel found out that model numbers

could not be copyrighted. So, instead of numbers, they used a trademark name, Pentium.

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6. The Sixth Generation, Part1 : ‘P6” Pentium Pro, Pentium II, Celeron and Pentium II Xeon

Intel Pentium Pro and Socket 8 CPU Accessories

CPU Cooling System

CPU Heat sink – It is use to cool down the CPU.

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Computer Ports and Connectors The first input and output devices you encounter are the external devices, such as the keyboard, video monitor, printer and so forth. Some of these devices have connectors that are the same as, or very similar to, the connectors used for other devices. In most cases plugging a new device into the wrong connector can damage the device or the system, so you need to know all the different connectors and which devices use them.

Connector Types

Keyboard port – connects the computer keyboard.

Video Out – Provides Video output for your computer.

USB (Universal Serial Bus)- connect computer peripherals such as mice, keyboards, PDAs, gamepads and joysticks, scanners, digital cameras, printers, personal media players, flash drives, and external hard drives.

LAN Port Keyboard Port

Video Out Audio Port

USB Port

http://en.wikipedia.org/wiki/Computer_peripheral

http://en.wikipedia.org/wiki/Mouse_%28computing%29

http://en.wikipedia.org/wiki/Computer_keyboard

http://en.wikipedia.org/wiki/Personal_digital_assistant

http://en.wikipedia.org/wiki/Gamepad

http://en.wikipedia.org/wiki/Joystick

http://en.wikipedia.org/wiki/Image_scanner

http://en.wikipedia.org/wiki/Digital_camera

http://en.wikipedia.org/wiki/Computer_printer

http://en.wikipedia.org/wiki/Media_player

http://en.wikipedia.org/wiki/USB_flash_drive

http://en.wikipedia.org/wiki/External_hard_drive

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The Computer Keyboard This is the most common input device. The keyboard allows the user to communicate with the PC through keystrokes that represent character data and commands. Keyboard Elements

1. Alphanumeric keys – the alphabet keys along with row numbers and special characters. These keys match those on a typewriter.

Alphabet keys

Punctuation and special characters

Actions keys

Character selection keys

Command control keys

Enter key

White space keys

Number/special character keys 2. Cursor control key – located on the right side of the alphanumeric keys, this

group of keys has two smaller groups of keys: the cursor function keys and cursor arrow keys.

3. Function keys- located across the top of a keyboard. 4. Numeric keypad – the number pad, which is located on the extreme right side of

nearly all modern keyboards, contains keys for ten numbers, as well as the four arithmetic functions. This can also be used as a cursor control pad by toggling the NUM LOCK key.

5. Toggle and Lock keys 6. Special purpose keys

ESC key

Print Screen key

Pause/break key 7. Window keys

Windows key

Application/Context key

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Keyboard Layout and Design 1. 83-keys PC/XT keyboard – the keyboard included in the original IBM PC and the

XT

2. 84-keys AT keyboard – it is a step closer to the standard keyboard layout used today

3. Enhanced 101- keys keyboard - it is the one most familiar to computer users today. Later models are really just enhancements of the design. This is the industry standard today.

4. Windows 104- keys keyboard – this is identical to 101-keys keyboard layout except for the addition of three new keys; two Windows keys, located between the CTRL and ALT keys on both sides and an Application key on the right side, next to the Windows key.

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5. Natural and Ergonomic Keyboard – this keyboard help relieve the stress caused by the position of the user’s hands and wrist and prevent repetitive stress injuries such as carpal tunnel syndrome.

Keyboard Elements/Layout

Alphanumeric keys – the alphabet keys along with row numbers and special characters. These keys match those on a typewriter.

Alphabet keys

Punctuation and special characters

Actions keys

Character selection keys

Command control keys

Enter key

White space keys

Number/special character keys Cursor control key – located on the right side of the alphanumeric keys, this group of keys has two smaller groups of keys: the cursor function keys and cursor arrow keys. Function keys- located across the top of a keyboard. Numeric keypad – the number pad, which is located on the extreme right side of nearly all modern keyboards, contains keys for ten numbers, as well as the four arithmetic functions. This can also be used as a cursor control pad by toggling the NUM LOCK key. Special purpose keys

ESC key

Print Screen key

Pause/break key Window keys

Windows key

Application/Context key

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Keyboard Layout Keyboard Connectors

1. The 5 pin DIN connector - this is the oldest of the keyboard connectors, also known as the AT form factor.

Pin Number Signal 1 Keyboard Clock 2 Keyboard Data 3 Unused 4 Ground 5 + 5v Power

2. The 6 pin Mini DIN Connector – it is designed to used six pins arranged in a

circular pattern around a plastic case, also known as PS/2 connector. Pin Number Signal

1 Keyboard Data 2 Unused 3 Ground 4 + 5v Power 5 Keyboard Clock 6 Unused

Alphanumeric keys

Function keys

Window keys

Cursor control

key

Special purpose keys

Numeric keypad

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3. The USB Connector – the universal serial bus is a multifunction peripheral bus

that is growing rapidly in popularity, and the keyboard is one of many devices that can use it.

4. IrDA (infrared) connector - it is a wireless keyboard.

Pointing Devices

1. Traditional Mice/Mouse - a palm-sized plastic housing with a rubber ball protruding from the bottom and a cord coming out the back.

2. Trackballs – it is an upside-down mouse with a larger than normal ball. Instead of rolling the ball by moving the whole mouse across a surface, you move the ball directly while the device itself remains stationary.

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3. IBM /Track Point – also known as Glide point mouse. It is created by IBM for its ThinkPad line of notebook computer to solve the pointing device problems.

4. Touch Pads – it is a rectangular pad located below the spacebar on a laptop keyboard. The pad senses the capacitance of your finger as you move it across the surface.

5. Joystick – a type of pointing device that is used primarily with game software on a PC.

6. Graphic Tablets – similar in conception with the touch pad, but it is larger and used with a stylus instead of your finger.

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Hard Disk Basics

A device that allows the user to store large amounts of data in the computer unit, sometimes refered also as the hard drive or Winchesters drive. .

Here is a typical hard-disk drive:

Inside the Hard Disk Platters Arm

The platters - These typically spin at 3,600 or 7,200 rpm when the drive is operating. These platters are manufactured to amazing tolerances and are mirror-smooth.

The arm - This holds the read/write heads and is controlled by the mechanism in the upper-left corner.

The Floppy Disk

The floppy disk drive (FDD) was the primary means of adding data to a computer until the CD-ROM drive became popular. In fact, FDDs have been a key component of most personal computers for more than 20 years.

Basically, a floppy disk drive reads and writes data to a small, circular piece of metal-coated plastic similar to audio cassette tape. In this article, you will learn more about what is inside a floppy disk drive and how it works. You will also find out some cool facts about FDDs.

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Optical drives

Optical drives uses laser light or electromagnetic waves near the light spectrum as part of the process of reading or writing data to or from optical discs

Portable Devices Devices that are compact and portable and often enable wireless high-speed broad band access, including laptops, personal digital assistants (PDAs), gaming consoles, mobile phones. Types of portable devices Laptop - a personal computer designed for mobile use and small and light enough to sit on one's lap while in use. A laptop integrates most of the typical components of a desktop computer, including a display, a keyboard, a pointing device (a touchpad, also known as a

http://en.wikipedia.org/wiki/Laser

http://en.wikipedia.org/wiki/Light_spectrum

http://en.wikipedia.org/wiki/Optical_disc

http://en.wikipedia.org/wiki/Personal_computer

http://en.wikipedia.org/wiki/Mobile_computing

http://en.wikipedia.org/wiki/Lap

http://en.wikipedia.org/wiki/Computer_hardware

http://en.wikipedia.org/wiki/Desktop_computer

http://en.wikipedia.org/wiki/Desktop_computer

http://en.wikipedia.org/wiki/Computer_display

http://en.wikipedia.org/wiki/Computer_keyboard

http://en.wikipedia.org/wiki/Touchpad

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track pad , and/or a pointing stick), speakers, and often including a battery, into a single small and light unit. Smart phones and PDA’s - PDA and Smart phones are examples of portable, hand-held devices that are becoming more popular. PDA’s offer features such as games, web surfing, e-mail, instant messaging, and many other features offered by PCs Basic parts of a laptop System Board – The system board is the main logic board in any laptop. All internal components are connected to the system board. This is one of the most expensive parts in a laptop

http://en.wikipedia.org/wiki/Pointing_stick

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Memory - temporary data storage. It’s a volatile type of memory. When you turn off the laptop, all the information stored in a RAM module is lost. Hard Drive - is the main storage of information in a laptop. All system files, personal files are stored inside the hard drive. Find the difference between SATA and IDE hard drives. Faster hard drive you have installed – faster data access you get.

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Processor – the brain of the computer. The processor is one of the main components in a laptop. Laptop processors are made mainly by Intel and AMD.

Optical Drive - The CD/DVD drive allows you to read/write data from/to a CD or DVD disc.

Cooling Fan -The cooling fan is a part of the cooling module in a laptop. The fan helps to cool down the processor when the laptop is turned on.

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Video card - In most modern laptops the video card is integrated into the system board. If the video card fails you have to replace the whole motherboard. In some laptops the video card is a discrete module and can be removed or replaced separately from the motherboard.

Audio and Sound - In most laptops the audio board is a part of the motherboard. If that’s the case, all audio board input/output components such as volume control, microphone jack and headphone jack are soldered directory to the motherboard.

Wireless card - The internal wireless card helps you to connect to the Internet without running a cable. Learn about different types of internal wireless cards and how they are connected to the motherboard.

CMOS Battery - The CMOS battery provides power to the CMOS chip when the laptop is

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turned off or disconnected form the wall outlet.

LCD screen - one of the most expensive parts in a laptop computer. The LCD screen mounts inside the display panel.If you accidentally cracked the screen, it has to be replaced. You cannot repair a cracked screen.

Inverter board - is a power supply for the backlight lamp inside the LCD screen. When inverter fails, the LCD screen goes very very dark and you barely can see any image on the screen. In most laptops the inverter board is mounted inside the display panel below the LCD screen.

Backlight lamp - is the main source of light in the LCD screen. The backlight lamp is mouted

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iside the screen. When the backlight lamp fails, you have to replace the whole LCD screen. It’s possible to replace just the lamp inside the screen but it’s very hard and has to be performed by an experienced technician.

Video cable - connectes the Laptop screen to motherboard. The video cable carries data signal for the LCD screen and power for the inverter board.

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Web Camera - Many modern laptops come with a web camera built into the display panel. The web camera is not a part of the LCD screen. The web camers is located on a separate board and can be replaced separately from the LCD.

Display hinges - connect two main parts of any laptop – the display panel and base assembly.

The AC/DC power adapter - converts high voltage AC power from the mains to low voltage DC power required by the laptop.

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Main Battery - a secondary source of power for a laptop. The battery gets charged while the laptop is plugged into the mains and keeps the laptop running when it’s unplugged from the mains.

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Directions: 1. Work in groups using a Personal Computer complete with peripherals. 2. Given the following tools, materials and equipment, identify the different parts of a personal computer starting from the front up to the internal parts of the PC. 3. Take turns doing this until every member of the group is done. 4. You will be assessed using the criteria in the score card below.



1 2 3 4 5

1. The components are identified successfully.

2. The peripherals are identified successfully.

3. Safety precautions are carefully observed.

4. Connecting the proper connections are performed.


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Multiple-choice: Test A:

1. What do you call the large printed circuit board inside your computer? a) CPU b) Mother board c) Video Card d) PSU 2. What type of input device that I common referred to as mice? a) Keyboard b) CPU c) Backplanes d) Mouse 3. What type of form factor that was released by Intel in 1995 was an

improvement over the LPX form factor? a) AT b) BABY AT c) NLX d) ATX 4. It defines a motherboard’s size, shape and how it is mounted to the case? a) Motherboard b) Form factor c) LGX d) PSU 5. It is also known as mainboard, system board or planar? a) Motherboard b) Motherboard Style c) CPU d) LXG

6. It i the skeletal frame work of your computer system. a) Cover b) Chassis c) Screws d) Power supply 7. It provides protection for the internal parts of the computer. a) Chassis b) Reset c) Case d) Cover 8. The part of the computer that provides power to the entire system? a) CPU b) Drive Bay c) Power Supply d) Reset 9. A button that allows the user to change the clock speed of old computers. a) Reset b) Turbo c) LED d) Power switch 10. The part of the chassis where you place the internal drives. a) Drive Bay b) Cover c) Chassis d) CPU

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Test B: Identification Direction: Identify the name of each connector found in the power supply. Write your answer on a separate sheet The power supply connectors

1.

2.

3.

4.

5.

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Program/ Course : Computer Hardware Servicing NC II Unit of Competency : Introduce Computer System Module Title : Introducing Computer System

Learning Outcome 3 : Maintain Computer System ASSESSMENT CRITERIA:

ASSESSMENT CRITERIA

1. Appropriate personal protective equipment are identified, used and checked based on the standard procedures.

2. Computer normal function is checked based on correct operation and safety. 3. Periodic maintenance of the equipment is performed following manufacturer’s

requirements. 4. Safety precautions are observed at all times.

RESOURCES:

Equipment/Facilities Tools & Instruments Supplies & Materials

Computer peripherals Desktop computers Laptop Computer OHS guidelines Phil. Environmental protection standards Monitors Motherboard Power supply Network device and cablings Hubs Switches LAN Cards Printers and Scanners Routers USB Flash Drives

Protective eye wear Wire stripper with cutter Pliers(Assorted) Screw drivers (Assorted) Soldering iron/gun De-soldering tool Flashlight Tweezers Mirrors Antistatic wrist wrap LAN Tester Crimping tool Software installer Work bench Magnifying glass

Floppy disk Compact Disk

REFERENCES:







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http://xnet.rrc.mb.ca/healthsafety/safeworkprocedures


http://www.empf.org/empfasis/aug04/prop.htm

http://www.lakeland.cc.il.us/~internal/policymanual/10fiscalaffairs/1026.POL.htm

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INFORMATION SHEET 3.1 Maintaining Computer System

Planning and preparing systematic maintenance procedure save time, money and frustration. It is a good idea and opportunity to learn the proper care and maintenance of your computer.

PC maintenance is an important topic for anyone who owns a PC. Looking after your PC properly ensures you of trouble-free use. Regular PC maintenance also keeps the machine’s performance optimal. TYPES OF MAINTENANCE PROCEDURE: 1. Hardware maintenance is the testing and cleaning of equipment. 2. Information system maintenance is the routine updating of master files, such as adding

and deleting employees and customers and changing credit limits and product prices. 3. Software or program maintenance is the updating of application programs in order to

meet changing information requirements. 4. Disk or file maintenance is the periodic reorganizing of disk files that have become

fragmented due to continuous updating.

Work place

Identify hazards and risks.

Safety policies are executed and carried out along with the task.

Following certain procedure is very important to perform a given operation or evolution or in reaction to a given event. The table below shows different elements and their corresponding performance criteria to be able to identify occupational health and safety hazards, and assess risk, as well as follow instructions and procedure in the workplace with minimal supervision. The students will also be capable of participating and contributing to OHS management issues.

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SAMPLE MAINTENANCE PLAN:

MONTHLY COMPUTER MAINTENANCE PLAN

JUNE JULY AUG SEPT OCT NOV DEC

Cleaning your computer

Disk space utilization

Scan for viruses

Check for hardware and software issues

Personal Protective Device There are tools and equipments used to protect the user and the computer system. Types of personal protective devices

1. Anti-static devices

2. Power surge protectors

3. Personal equipments

Personal Equipment

1. Small paint brush

2. Screw drivers

3. Pliers and tweezers

4. Compressed air

5. Handheld vacuum

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Sample Hardware Inspection Checklist Computer no:____________________

Component

Working

Not Working

Monitor

Keyboard

Mouse

Speaker

Printer

Voltage regulator

Sample Software Inspection Checklist Computer no:____________________

Software

Working

Not Working

Applications

Operating System

User programs

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INFORMATION SHEET 3.2 Cleaning Your Computer System Appropriate cleaning procedures

Proper routine cleaning is the easiest, least expensive way to protect and to extend the life of a laptop. It is very important to use the right products and procedures when cleaning a laptop. Always read all warning labels on the cleaning products. The components are very sensitive and should be handled with care. Consult the compuer manual for additional information and cleaning suggestions.

Keyboard Cleaning Procedures

1. Turn off the computer

2. Disconnect all attached devices.

3. Disconnect laptop from the electrical outlet.

4. Remove all installed batteries.(for laptops)

5. Wipe the keyboard with a soft, lint-free cloth that is lightly moistened with water or computer-screen cleaner.

Ventilation Cleaning Procedures

1. Turn off the computer/laptop.


3. Disconnect computer from the electrical outlet.

4. Remove all installed batteries. .(for laptops)

5. Use compressed air or a non-electrostatic vacuum to clean out the dust from the vents and the fan behind the vent.

6. Use tweezers to remove any debris.

LCD Cleaning Procedures

1. Turn off the computer..




5. Wipe display with a soft, lint-free cloth that is lightly moistened with a mild cleaning solution.

CAUTION: Do not spray cleaning solution directly onto the LCD display. Use products specifically designed for cleaning LCD displays.

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Touch Pad Cleaning Procedures

1. Turn off the computer.




5. Wipe surface of touch pad gently with a soft, lint-free cloth that is moistened with an approved cleaner. Never use a wet cloth.

The small screen of a PDA or Smartphone requires special care. The user operates these devices by touching the screen with a stylus. If dirt is present, the PDA may not accurately detect the stylus position or movement. The dirt can also scratch the screen. Clean the screen with a small amount of non-abrasive cleaning solution on a soft cloth. To protect the screen surface from a stylus, use self-adhesive screen covers.

CAUTION: Use a soft, lint-free cloth with an approved cleaning solution to avoid damaging laptop surfaces. Apply the cleaning solution to the lint-free cloth, not directly to the laptop.

Floppy Drive Cleaning Procedures

Use a commercially-available cleaning kit to clean a floppy drive. Floppy drive cleaning kits include pre-treated floppy discs that remove contaminants from the floppy drive heads that have accumulated through normal operation.

1. Remove all media from the floppy drive.

2. Insert the cleaning disc and let it spin for the suggested amount of time.

Optical Drive Cleaning Procedures

Dirt, dust, and other contaminants can collect in the optical drives. Contaminated drives can cause malfunctions, missing data, error messages, and lost productivity.

1. Use a commercially-available CD or DVD drive cleaning disc. Many floppy disc cleaning kits include an optical disc cleaner. Like the floppy disc cleaner, optical disc cleaner kits contain a cleaning solution and a non-abrasive disc that is inserted into the optical drive.

2. Remove all media from the optical drive.

3. Insert the cleaning disc and let it spin for the suggested amount of time to clean all contact areas.

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Cleaning a CD or DVD Disc Inspect the disc for scratches. Replace discs that contain deep scratches; they may cause data errors. If you notice problems such as skipping or degraded playback quality with your CDs or DVDs, clean the discs. Commercial products are available that clean discs and provide protection from dust, fingerprints, and scratches. Cleaning products for CDs are safe to use on DVDs.

1. Hold the disc by the outer edge or by the inside edge.

2. Gently wipe the disc with a lint-free cotton cloth. Never use paper or any material that may scratch the disc or leave streaks.

3. Wipe from the center of the disc outward. Never use a circular motion.

4. Apply a commercial CD or DVD cleaning solution to the lint-free cotton cloth, and wipe again if any contaminates remain on the disc.

5. Allow the disc to dry before it is inserted into the drive.

Computer operating environment

An optimal operating environment for a omputer is clean, free of potential contaminants, and within the temperature and humidity range specified by the manufacturer.

It is important to transport or ship laptops carefully. Use a padded computer case to store your laptop. When you carry it, use an approved computer bag. If the

Laptops and computers are transported to many types of environments. Dust particles, temperature, and humidity can affect the performance of a laptop.

Follow these guidelines to help ensure optimal operating performance from your computers/ laptop:

Clean the PC frequently to remove dust and potential contaminants.

Do not obstruct vents or airflow to internal components. A laptop can overheat if air circulation is obstructed.

Keep the room temperature between 45 to 90 degrees Fahrenheit (7 to 32 degrees Celsius).

Keep the humidity level between 10 to 80 percent.

CAUTION: Use a soft, lint-free cloth with an approved cleaning solution to avoid damaging laptop surfaces. Apply the cleaning solution to the lint-free cloth, not directly to the laptop.

Temperature and humidity recommendations will vary by laptop manufacturer. You should research these recommended values, especially if you plan to use the laptop in extreme conditions

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Equipment, Tools, and Materials: Personal Computer complete with peripherals Cleaning tools Directions: 1. Groups yourselves into five. The teacher will assign a computer unit to your group. 2. Create checklist for your hardware and software. 3. Given the following tools, materials and equipment, inspect and clean your computer hardware. 4. Take turns in doing the task. 5. You will be assessed using the criteria in the score card below.



1 2 3 4 5

1. Proper inspection is performed.

2. The peripherals are checked successfully.

3. Safety precautions are carefully observed.

4. Proper cleaning of devices are performed.


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Written Answer the following questions in your answer sheet.

1. Why do we need to perform a system inspection? 2. Why is it important to clean your computers hardware?

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Multiple-choice:

1. What do you call the large screen in a laptop? a) CPU b) Mother board c) Video Card d) LCD 2. What type of motherboard design that is common in large PC network

servers and on other computers on which the processor is upgraded frequently?

a) Motherboard b) CPU c) Backplanes d) ATX 3. It serves as the power supply for your laptop? a) AT b)Power Supply c) CMOS d) Battery 4. It defines a motherboard’s size, shape and how it is mounted to the case? a) Motherboard b) Form factor c) LGX d) PSU 5. It is also known as mainboard, system board or planar? a) Motherboard b) Motherboard Style c) CPU d) LXG

6. It i the skeletal frame work of your computer system. a) Cover b) Chassis c) Screws d) Power supply 7. It provides protection for the internal parts of the computer. a) Chassis b) Reset c) Case d) Cover 8. The part of the computer that provides power to the entire system? a) CPU b) Drive Bay c) Power Supply d) Reset 9. A button that allows the user to Turn off the computer. a) Reset b) Turbo c) LED d) Power switch 10. The part of the chassis where you place the Motherboard drives. a) Drive Bay b) Cover c) Chassis d) CPU

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Self Check 1.1 1. Z 2. V 3 Y 4. X 5. W Self Check 1.2 1. C 2. B 3. B 4. B 5. B Self Check 2.1 1. Surge Suppressor 2. UPS 3. Anti-static Bag 4. Anti-static Wrist strap 5. AVR Self Check 2.2 1. K 2. L 3. I 4. J 5. H

Self Check 2.3 Test A: 1. B 2. D 3. C 4. B 5. B 6. B 7. D 8. C 9. B 10. A Test B: 1. 4 pin Berg Connector 2. 4 pin Molex Connector 3. 20 pin Molex Connector 4. 4 pin Molex Connector 5. 6 pin AUX Connector Post and Pre Test 1. B 2. A 3. C 4. C 5. A 6. B 7. A 8. C 9. D 10. C

PC HARDWARE SERVICING - Weeblypchssepnaskto12.weebly.com/uploads/2/2/8/6/22868856/module_0... · PC HARDWARE SERVICING ... Hand Tools. ... 1.1 Hardware: The mechanical and electronic

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