PC Support & Repair Chapter 1 Intro to the Personal Computer
PC Support & RepairChapter 1Intro to the Personal Computer
Objectives• After completing this chapter, you will meet these
objectives:▫Explain IT industry certifications. ▫Describe a computer system. ▫ Identify the names, purposes, and characteristics of:
Cases and power supplies. Internal components. Ports and cables. Input devices. Output devices.
▫Explain system resources and their purposes.
A+ Certification?•What is it?▫Describe the cert, tests, jobs, etc.
Computer System•What does it consist of?
Case•Form factor▫Desktop or tower▫Other names: chassis, box
•Protects internal components•Case fans keep equipment cool•Case grounds equipment
How to Choose a Case•Motherboard must fit it•Components you need must fit in it•Power Supply connection & rating• Looks, lights, etc• LED status lights•Venting▫Some have many vents for air flow
Power Supplies•Converts AC (wall) to DC (computer)▫DC is lower voltage
•Rated in Watts▫250-650 watts avg.▫Add up components▫Get more than you need
•What does a UPS do?
Power Supplies•What’s this?
Component Connectors•Keyed▫Fits one way only
•Color Cables & Power▫Yellow +12v▫Blue -12v▫Orange 3.3v▫Red +5v▫White -5v▫Black 0v GROUND
Power Supply to Motherboard•Current: 20 or 24 pin
•Older: P8 & P9▫Could plug in
wrong & fry MB
Molex Connector•CD/DVD & HD
•4 pin
•Only fits one way
Berg Connector•Floppy Drive•AGP Cards•For low power items
Power Supplies•What’s this?
•NEVER OPEN!!
•CAPACITORSHOLD A CHARGEFOR A LONGTIME!!
Project•Power Supply Handout▫Identify connectors▫Answer questions
•Find a power supply Handout▫Use the calculator
Motherboards• Large circuit board▫AKA system board or backplane▫Buses to pass data
•Form Factor▫Size & shape
AT Form Factor- OLD•Old desktops
•P8 & P9
•Too big
•Power-switched
•Was also Baby AT
ATX Form Factor- CURRENT•Current•Smaller▫Mini ATX▫Micro ATX
•20-pin PS connector• Layout better•No OFF switch
BTX Form Factor- CURRENT•2003
•Better airflow
•7 expansion slots
Motherboards & Chipsets•Controls how hardware interacts with CPU & MB▫Sets max amount of memory that can be installed▫Defines type of connectors on MB
•Northbridge▫RAM, Video, CPU
•Southbridge▫Hard drives, sound card,
USB ports, and other I/O ports
Project•Compare/contrast Motherboards
Review•What determines how much memory can be
installed on a motherboard?▫Chipset
•What does the Northbridge chipset control?▫Access to RAM, Video Card, CPU
•What does the Southbridge chipset control?▫HD, USB, Sound Card, I/O ports
•AT or ATX…Which is a current standard?▫ATX
Review•Other than ATX, what is another current motherboard
form factor?▫BTX
•Which of these would determine by the form factor? SELECT 2▫Color, Size, How much memory it can take, shape
•How many pin PS connector is on today’s MB?▫20
•Older AT MB connectors included what two?▫P8 & P9
CPU• Intel & AMD•Cycles per second▫MHz (millions), GHz (billions)
•Fits certain socket or slot▫Pins insert into socket with ZIF▫Newer CPU has no pins
•Many types of sockets▫Fit certain CPU, see chart
• Look at slide 1.4.2
CPU•Executes instructions•While processing data, next set of instructions are
store in cache memory•Two architectures (how completes instructions)▫Reduced Instruction Set Computer (RISC)
Small set of instructions designed to execute rapidly Old Apple CPUs
▫Complex Instruction Set Computer (CISC) Broad set of instructions in fewer steps per operation Intel & AMD
CPU• Front Side Bus▫Amount of data CPU can process▫32 or 64-bit
•Overclocking▫Speeding up CPU▫Could damage it
• Throttling▫Slowing down CPU
•Multi-core▫More than one core on a single chip▫Triple-core is a quad with one core disabled
Cooling Systems•Stay cool▫Heat will make it run
slower & damage it•Case fan•Heat sink & fan for CPU•Graphics card can have
fans for their GPU•Water-cooling
ROM•On MB• Instructions for boot & load OS•Non-volatile•Can’t modify/erase normally•ROM- info stored when made OLD•PROM- info stored after made OLD•EPROM- info stored after made; erased with UV light•EEPROM- can be erased/rewritten on board (flash)
RAM•Temp & volatile
•SRAM used for cache
•SDRAM
•DDR3 SDRAM▫Faster than DDR2▫Less power & heat
Memory Modules•SIMM▫30 or 72 pin
•DIMM▫168 pin SDRAM▫184 pin DDR▫240 pin DDR2
•SODIMM▫Laptops▫72 or 144 pin
FalseFalse
Memory Types & Speeds
Cache Memory•SRAM•CPU gets faster access to data
• L1▫Built into CPU
• L2 ***▫Next to CPU
• L3▫Next to CPU▫Used with high end CPU
Memory Error Checking•Non parity ***▫Kind used today▫No error checking
•Parity▫One bit checks for errors
•ECC▫Server▫Can detect multiple bit errors & correct them
Project•Research types of RAM•CPU cache
Adapter Cards•Name & ID different cards
•PCI 32 or 64 bit
•AGP 32 bit video
•PCIe replacing AGP
• ISA OLD 8 or 16 bit
Motherboard Slots
Floppy Drive•Magnetic storage•720KB OLD•1.44MB•A:
Hard Drive•Magnetic storage▫Spinning platters
•C:•GB•RPM
•SSD▫No moving parts▫Flash▫Faster access, low power
Optical Drive•CD, DVD, BD
•CD= 700MB
•DVD= 4.3GB single layer▫8.5GB dual layer
•BD= 25GB single layer▫50GB dual layer
Drive Interfaces• IDE OLDER 40 pin connector•EIDE OLDER 40 pin connector▫For drives bigger than 512MB▫40/80 conductors in wire
•SATA 7 pin connector•eSATA EXTERNAL•SCSI▫Can connect up to 15 drives▫50, 68 or 80 pin connector
RAID•Stores data across many hard drives▫Backup
•Parity –Detect data errors•Striping –Writes data across multiple drives•Mirroring –Storing duplicate data to a second drive
•RAID 1 mirroring (full redundancy)•RAID 5 striping
Project•Worksheet 1.4.7
•Extra Activity Handout
Ports•Name ‘em…•Serial▫9 pin▫Transmits one bit at a time SLOW!
•USB▫127 devices per port (using hubs)▫1.1= 12Mbps▫2.0= 480Mbps▫3.0= up to 4.8Gbps
Ports•Firewire▫Supports up to 63 devices per port▫IEEE1394a up to 400Mbps, 4 or 6 pin
•Parallel▫DB25, printer side is Centronics 36 pin▫IEEE1284▫8 bits at a time
Ports•SCSI▫End point in chain must be terminated
•Network▫RJ45▫Fast Ethernet is 100Mbps▫Gigabit is 1000Mbps▫328ft or 100m MAX cable length
Ports•PS/2▫6 pin female
•Audio▫In, out, MIC, S/PDIF, TosLink,
MIDI •Video▫VGA, DVI, HDMI, S-Video, Component
Input Devices•Data goes into the computer•Name some input devices
•What is a KVM?
Output Devices•From the computer to user•Name some output devices
• Let’s look at monitors
Displays•CRT• LCD•DLP
•Pixel•Dot Pitch▫Distance between pixels
•Native Resolution▫# of pixels▫1280 x 1024 (h x v)
Display Resolutions
Multiple Monitors on One Computer•Need two video ports▫Add another card (or two)
System Resources•Communication between CPU & other components• Interrupt Requests (IRQ) ▫Assigned automatically today▫Requests info from CPU▫16 IRQ’s (0-15)▫Each component has its own #
System Resources• Input/Output (I/O) Port Addresses▫Communicate between devices & software▫Over 65,000 ports▫
•Direct Memory Access (DMA)▫High-speed devices talk to memory▫Avoids bugging the CPU
End of Chapter Review
PC Support & RepairChapter 1Intro to the Personal Computer