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Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting Essential Hardware Chapter 3 © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Overview Fourth Edition (Exam 220-802) • In this chapter, you will learn how to – Troubleshoot CPUs – Troubleshoot RAM – Troubleshoot BIOS and motherboards – Troubleshoot power supplies © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting CPUs © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Troubleshooting CPUs Fourth Edition (Exam 220-802) • Overheating—can cause system to not start or to lock up. Newer CPUs will usually shut themselves down before overheating. – Too much heat dope (thermal paste) can impede the flow of heat from the CPU to the heat sink and cause the CPU to heat up rapidly. – Not enough thermal paste can cause the CPU to heat up and shut down. – Faulty fan power connection can cause the CPU to heat up and shut down. – Heating may take longer and cause problems after boot and OS load © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting CPUs (continued) – Environmental heat/lack of adequate ventilation can cause CPU heat-up and shutdown • Catastrophic failure – May cause Windows Stop error (Blue Screen of Death) – May cause PC to shut down or go black – May burn up components © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting CPUs (continued) Figure 1: Blue Screen of Death © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting RAM © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Memory Errors Fourth Edition (Exam 220-802) • Memory errors can include – – – – – Parity errors ECC error messages System lockups Page faults Other error screens in Windows © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Memory Errors (continued) Fourth Edition (Exam 220-802) • Write down memory error addresses. – If the error returns with the same address each time, it is likely a RAM stick failure. • If the error address changes, it is likely not a RAM failure. • System lockups and page faults often indicate RAM problem. • RAM and parity errors can trigger a nonmaskable interrupt (NMI) that results in the Blue Screen of Death (BSoD). © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Memory Errors (continued) Fourth Edition (Exam 220-802) Figure 2: Windows error message © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Memory Errors (continued) Fourth Edition (Exam 220-802) • Not all intermittent errors are caused by bad RAM – Dying power supply, electrical interference, and buggy applications or hardware can also produce intermittent errors. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Testing RAM Fourth Edition (Exam 220-802) • Several RAM testing devices are available, but many are expensive. • Can replace one stick at a time until problems disappear. • Use a software-based tester such as Memtest86. • Windows 7 includes the Memory Diagnostics Tool, which can automatically scan your computer’s RAM when you encounter a problem. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Testing RAM (continued) Fourth Edition (Exam 220-802) Figure 3: Memtest86 in action © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Power-on Self Test (POST) © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) ROM Initiates the POST Process • Upon boot, the ROM initiates the POST process. • The POST routine sends out a message to all assumed components to initiate self-tests. – This determines whether the components are working properly. The quality of POST diagnostics is determined by the component. • If a component fails self-diagnostics, the POST process halts and sends an error message. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Beep Codes Fourth Edition (Exam 220-802) • Before and during the video test: beep codes • If video is missing or faulty, you’ll hear one long beep followed by three short beeps. • If RAM is missing or faulty, you’ll hear a rather alarming beeping/buzzing that will repeat as long as the computer is on. • If the POST completes successfully, you’ll hear one or two short beeps. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Text Errors Fourth Edition (Exam 220-802) • Once the video is determined to be good, errors can be displayed. • Errors are usually displayed in clear text, though they can sometimes be rather cryptic. Figure 4: POST text error messages © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs POST Cards Fourth Edition (Exam 220-802) • The small expansion card installs into an available slot – Used to monitor the POST and identify whether a piece of hardware is causing startup issues • Note the light-emitting diode (LED) display to see what device POST is currently checking – Refer to the two-digit hex code on the LED display to determine the faulty POST code • Look up the code in the companion manual—it can help identify the faulty component © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs POST Cards (continued) Fourth Edition (Exam 220-802) • If the PC passes POST, the problem is more likely a software problem • POST cards used to be an essential tool for techs – Today they are rarely used, and then only on a “dead” PC to determine at which level it’s dead – If the POST card shows no reading, the problem is before the POST and must be related to the CPU © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs POST Cards (continued) Fourth Edition (Exam 220-802) Figure 5: POST card in action © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs The Boot Process Fourth Edition (Exam 220-802) • The power supply checks for proper voltage. – If the proper voltage is found, the power supply sends a signal through the power-good wire. – This awakens the CPU, which in turn sends a builtin memory address, which is the first line of the POST program on the system ROM. • The ROM begins the POST routines. • Once the POST is passed, the ROM begins the boot process (the bootstrap loader) by looking for an operating system according to the CMOS settings. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs The Boot Process (continued) Fourth Edition (Exam 220-802) Figure 6: CMOS boot order © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs The Boot Process (continued) Fourth Edition (Exam 220-802) • The CMOS settings tell it which device to try to boot from. – It looks at the boot sector of that device (floppy, CD-ROM, hard drive, etc.) and tries to load an operating system. • Once the boot process begins, control is handed over to the operating system. • Some BIOSs allow the PC to use a preboot execution environment (PXE). – A PXE enables you to boot a PC without any local storage by retrieving an OS from a server over a network. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Care and Feeding of BIOS and CMOS © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Losing CMOS Settings Fourth Edition (Exam 220-802) • The battery provides continuous trickle charge to hold data. It also keeps the clock running. • If the battery dies or is removed, all data is lost and the system returns to factory defaults. • Common errors – – – – CMOS configuration mismatch CMOS date/time not set No boot device available CMOS battery state low © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Losing CMOS Settings (continued) • Common reasons for losing CMOS data – – – – – – Pulling and inserting cards Touching the motherboard Dropping something on the motherboard Dirt on the motherboard Faulty power supplies Electrical surges • If settings keep resetting, replace the battery. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Losing CMOS Settings (continued) Figure 7: A CMOS battery © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Flashing ROM Fourth Edition (Exam 220-802) • Flash ROM chips can be reprogrammed. • Download the program from the manufacturer and follow the instructions. • Typically insert a removable disk of some sort (usually a USB thumb drive) containing an updated BIOS file. • Only flash the BIOS if necessary. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Flashing ROM (continued) Fourth Edition (Exam 220-802) Figure 8: ROM-updating program for an ASUS motherboard © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting Motherboards © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Troubleshooting Symptoms Fourth Edition (Exam 220-802) • Catastrophic failure – System will not boot. – Although uncommon, most motherboards will fail (if they’re going to) within the first 30 days due to manufacturing defects, called burn-in failure. – Electrostatic discharge is the other most common cause. – To fix, replace the motherboard. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs More Troubleshooting Symptoms Fourth Edition (Exam 220-802) • Component failure – Intermittent problems – Examples include a hard drive that shows up in CMOS but not in Windows – Most common causes are electrical surges and ESD – Sometimes a BIOS upgrade may solve this problem if the issue is lack of BIOS support for a newer technology – Fixes include replacing the component with an add-on card or flashing the BIOS © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) More Troubleshooting Symptoms (continued) • Ethereal symptoms – Things just don’t work all the time. – PC reboots itself for no apparent reason. – Blue Screens of Death appear as the computer crashes. – Causes include faulty components, buggy device drivers or application software, slight corruption of the operating system, and power supply problems. – Fixes include flashing the BIOS or replacing the motherboard. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Techniques Fourth Edition (Exam 220-802) • Isolate the problem by eliminating potential factors. • Check, replace, verify good component. – If the hard drive doesn’t work, try a different hard drive, or try the same hard drive with a different motherboard. • If the new hard drive works, you know it wasn’t the motherboard. • If the same hard drive with a different motherboard works, you can suspect the motherboard. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Options Fourth Edition (Exam 220-802) • There are a couple of options for dealing with a motherboard failure. – Catastrophic failure: replace the motherboard. – Component failure: consider an add-on card to replace the device. • Consider a BIOS update if the device issue is a problem other than physical damage. Figure 9: Adaptec PCIe SATA card © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fourth Edition (Exam 220-802) Troubleshooting Power Supplies © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Troubleshooting Power Supplies Fourth Edition (Exam 220-802) • Power supplies fail in two ways – Sudden death • When the fan doesn’t turn and no voltage is present • Computer simply stops working – Slowly over time • Intermittent errors • Output voltages may exceed specs (±10%) © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Lab – Power Supply Test Fourth Edition (Exam 220-802) 1. Set the multimeter to test DC. 2. Turn on the PC. 3. Put the black lead onto any black wire connection. 4. Put the red lead onto a colored wire. • 12 V ± 10 percent – 10.8 to 13.2 V – If readings are outside tolerance and symptoms exist, replace power supply. © 2013 The McGraw-Hill Companies, Inc. All rights reserved Figure 10: Testing one of the 5-V DC connections • 5V ± 10 percent – 4.5 to 5.5 V • 3.3 V ± 10 percent – 2.97 to 3.63 V Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Power Supply Test Fourth Edition (Exam 220-802) • Power supplies need a load – Plug into motherboard – Plug into tester • Check power switches – If faulty, can turn on with motherboard jumper Figure 11: ATX power supply tester © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs When Power Supplies Die Slowly Fourth Edition (Exam 220-802) • Intermittent problems – Sometimes occur, sometimes don’t – You could measure voltage now and it’s good; ten minutes later, system crashes • A dying power supply can cause – Random lockups and reboots – Sporadic boot-up difficulties • When you encounter intermittent symptoms, consider replacing the power supply © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fuses and Fire Fourth Edition (Exam 220-802) • Circuit breakers are heat-sensitive – Sense when amperage exceeds threshold – Breaks the circuit to stop flow of electricity • Fuses blow for a reason – Power supply is malfunctioning – As a designed safety precaution, fuses blow (break) to stop circuit • Alternative is a possible fire © 2013 The McGraw-Hill Companies, Inc. All rights reserved Mike Meyers’ CompTIA A+® Guide to 802: Managing and Troubleshooting PCs Fire Extinguishers Fourth Edition (Exam 220-802) • Class A – Ordinary combustibles such as paper and wood • Class B – Flammable liquids such as gasoline • Class C – Live electrical equipment • Use only Class C extinguishers on electrical fires © 2013 The McGraw-Hill Companies, Inc. All rights reserved