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A+ Guide to Hardware, 4e
Chapter 2
PC Repair Fundamentals
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You’re Special
Objectives
• Learn about tools you’ll need as a PC support technician
• Learn how to develop a preventive maintenance plan and what to include in it
• Learn how to work inside a computer case
• Learn what happens when you first turn on a PC before the OS is loaded
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Objectives (continued)
• Learn how to approach and solve a PC problem
• Learn how to troubleshoot a failed boot before the OS is loaded
Introduction
• Basic repair skills
– Developing a maintenance plan
– Implementing a maintenance plan
– Working inside a computer case
– Following sequence of events that occur at startup
• Advanced repair skills
– Using common-sense guidelines to solve problems
– Interviewing a user
– Determining if a problem occurs before or after boot
– Troubleshooting and solving a problem of a failed boot
PC Support Technician Tools
• Help you maintain a computer
• Help you diagnose and repair computer problems
• Criteria for choosing tools:
– Level of PC support you expect to provide
– Amount of money you can spend
• Some essential tools:
– Ground bracelet, ground mat, or ground gloves
– Torx screwdriver set
– Recovery CD, DVD, or floppy disk for target OS
• Store tools in toolbox for PC troubleshooting
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Recovery CDs
• Used to boot a system
• Also used to repair and reinstall Windows
• Primary recovery CD sources
– PC manufacturer (preferred)
– Operating system distributor, such as Microsoft
• Some hard drives have a hidden recovery partitions
– A hidden partition can be used to reinstall Windows
– A utility for creating recovery CDs may be provided
– Access hidden utilities by pressing a Fn key at startup
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Loop-Back Plugs
• Used to test various ports
– Some port types: serial, parallel, USB, network
• How to use a loop-back plug
– Plug in the loop-back plug
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– Run the software that comes with the plug
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Cleaning Pads and Solutions
• Various types are designed for specific uses
• Example: contact cleaner
– Cleans contacts on expansion cards
• Warning: solutions may be flammable and/or toxic
• Sources of safety and emergency instructions:
– Side of the can of solution
– Material safety data sheet (MSDS)
• Adhere to safety procedures of your employer
– Example: fill out an accident report (if required)
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Post Diagnostic Cards
• Report computer errors and conflicts at POST
• How to use a POST diagnostic card:
– Install card in an expansion slot on the motherboard
– Attempt to boot your system
– Record any error codes appearing in LED panel
– Look up the entry associated with the error code
• Examples of Post diagnostic cards:
– PCI Error Testing/Debug Card by Winic Corporation
– POST card V3 by Unicore Software, Inc.
– Post Code Master by MSD, Inc.
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Personal Computer Preventive Maintenance
• Preventive maintenance reduces number of problems
• Goals of preventive maintenance plans:
– Prevent failures
– Reduce repair costs
– Reduce downtimes
• Goal of disaster recovery plan: manage failures
• Some causes of PC failure: heat, dust, spills, viruses
When a PC is your Permanent Responsibility
• Tasks and procedures to prepare for troubleshooting
– Keep good backups of data and system files
– Document all setup changes, problems, and solutions
– Protect the system against viruses and other attacks
• Always use a firewall (software or hardware barrier)
• Install and run antivirus software
• Keep Windows Updates current
– Physically protect your equipment
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Creating a Preventive Maintenance Plan
• Plan based on history or pattern of malfunctions
– Example: PCs in dusty areas need more maintenance
• Goals common to maintenance plans
– Extend the working life of a PC
– Anticipate problems that could disrupt service
– Ensure data is secure and backed up
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– Provide support to PC users
• Basic steps involved in designing a plan
– Define your overall goals
– Incorporate procedures for achieving goals
Dealing with Dust
• Dust accumulates in layers over components
• Two major problems due to dust blankets
– PC components directly overheat
– Cooling fans jam, also resulting in overheating
• Maintenance task: remove the layer of dust
• Two tools used to remove dust:
– Antistatic vacuum
– Compressed air
Preparing a Computer for Shipping
• Adverse factors to consider:
– Rough handling
– Exposure to water, heat, and cold
– Misplacement or theft of computer
• Some shipping guidelines to follow:
– Backup the hard drive onto a backup medium
– Remove inserted disks, tape cartridges, or CDs
– Coil and secure all external cords
– Separately wrap hardware components
– Purchase insurance on the shipment
Disposing of Used Equipment
• Various guidelines for disposing of equipment:
– Table 2-2
– Manufacturer documentation
– Local environmental regulators
• Danger posed by monitors and power supplies
– Residual charge in capacitors can cause shock
– Modern devices discharge if unplugged for 60 minutes
– Older devices may require discharge with a probe
• Destroy secondary storage devices with sensitive data
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Uncovered Vent
Dirty Fan
How to Work Inside a Computer Case
• Objective: dismantle a computer, put it back together
• Some safety precautions to follow:
– Make notes that will help you backtrack
– Keep screws and spacers orderly
– Do not stack boards on top of each other
– Do not touch the chips on circuit boards
– Do not use a graphite pencil to change DIP settings
– Turn off the power, unplug and ground the computer
– Do not remove covers of monitors or power supplies
– Keep components away from hair and clothing
Static Electricity
• Build-up of charge due to absence of conductors
• Electrostatic discharge (ESD)
– Due to dissimilar electrical surfaces making contact
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– Only 10 volts of ESD can damage PC components
– Walking across carpet generates up to 12,000 volts
• Two types of damage: catastrophic and upset failure
• Tool and methods for grounding yourself and the PC
– Ground bracelet, ground mats, static shielding bags, antistatic gloves
• If working inside a monitor, do not ground yourself
Anti-Static Mat
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Steps to Take Apart a Computer
• Essential tools:
– Ground bracelet
– Phillips-head screwdriver
– Flat-head screwdriver, paper, and pen
• Follow safety precautions at all times
• Summary of Steps 1 - 4
– 1. Enter CMOS and write down customized settings
– 2. Power down the system, unplug all components
– 3. Put the computer on a good-sized table
– 4. Remove the cover of the PC
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4: Remove Cover
Steps to Take Apart a Computer (continued)
• Summary of steps 5 - 11
– 5. Diagram cable connections and switch settings
– 6. Identify cables connecting drives to motherboard
– 7. Remove the cables to all drives
– 8. Remove the expansion cards
– 9. Remove the motherboard (or drives)
– 10. Remove the power supply from the case
– 11. Remove each drive (if not already removed)
• Lets look at each step in detail
5. Diagram cable connections
and switch settings
6. Identify cables connecting drives to motherboard
8: Remove Expansion Cards
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9: Remove the motherboard
from the case
10. Remove the power supply
from the case
11: Remove all Drives
Outside Help
• Many sites on the web can help show how to take a computer apart
• http://www.fonerbooks.com/r_mother.htm
• http://www.pcworld.com/article/id,103811-page,2-c,motherboards/article.html
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Steps to Put a Computer Back Together
• 1. Install power supply, drives, motherboard, cards
• 2. Connect all data and power cables
• 3. Plug in the keyboard, monitor, and mouse
• 4. Ask instructor to check work (if in a classroom)
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• 5. Turn on the power and check PC functions
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Understanding the Boot Process
• Key learning objectives
– Know how to boot a PC
– Understand what happens first when a PC is turned on
– Understand how an operating system is loaded
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Booting a Computer
• Process that drives a computer to a working state
• Hard (cold) boot: turn the power switch on
• Soft (warm) boot: allow the OS to reboot
• How to soft boot Windows XP
– Click Start
– Click Turn Off Computer
– Click Restart
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Choosing Between a Hard Boot and a Soft Boot
• Hard boots are more stressful on machines
– Power surges through system when PC is turned on
• Reasons to choose a soft boot over hard boot
– Less stressful on the machine
– Faster due to skipping initial steps
• Some computers have a soft and hard power switch
– Soft power switch shuts down and restarts Windows
– Hard power switch cuts power and restarts machine
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The Startup BIOS Controls the Beginning of the Boot
• The startup BIOS gets a system up and running
• Four phases of the boot process:
– BIOS runs the POST and assigns system resources
• POST: power-on self test
– BIOS searches for and loads an OS
– OS configures system and completes its own loading
– Application software is loaded and executed
• Beep Codes
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Changing the Boot Sequence
• BIOS looks to CMOS RAM to locate the OS
• Boot sequence: order of drives checked for an OS
• Change boot sequence using CMOS setup utilities
• Access CMOS setup utilities when PC is turned on
– Example: press F8 before Windows screen appears
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How to Troubleshoot a PC Problem
• Assume the attitude of an investigator
• Do not compound the problem by your own actions
• Look at the problem as a learning opportunity
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• Ask questions until you understand the problem
• Believe that you can solve the problem
Steps to Solving a PC Problem
• Key advice:
– Ask good questions
– Document the process
• Four-step problem solving process:
– Step 1: Interview the user
– Step 2: Back up data
– Step 3: Solve the problem
– Step 4: Verify the fix and document the solution
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Troubleshooting a Failed Boot
• It takes time to acquire troubleshooting skills
• Hands-on training: troubleshooting a failed boot
My Computer Won’t Boot
• First step: maintain your calm
• Second step: develop a game plan
• Figure 2-45 provides a procedure
– Plan is driven by a set of yes-no questions
– Example: Does the PC boot properly?
• If no, troubleshooter is directed to another question
• If yes, troubleshooter is directed to stop (for now)
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Troubleshooting Major Subsystems Used For Booting
• Categories of troubleshooting steps in Figure 2-45
– The electrical subsystem
– Essential hardware devices
• The motherboard, memory, and the CPU
– Video
– Reading from the hard drive
• Key aides: tables identifying error codes
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Summary
• Some PC repair tools: recovery CDs, screwdrivers, POST, cleaning pads and solutions,
diagnostic cards
• Preventive maintenance plans extend the life of a PC
• Follow an organization’s preventive maintenance plan, or develop one if it does not exist
• Computers present chemical and electrical hazards
• Protect components in case from ESD by grounding yourself and the PC
Summary (continued)
• Assembling and reassembling a PC prepares the technician for actual repair work
• Startup BIOS controls when the boot process begins
• Four step boot process: POST, loading the OS, OS initializing itself, loading and executing
applications
• Expert troubleshooters ask good questions
• Before tackling a problem, develop a game plan
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