Chapter 15 PC Troubleshooting 647
Problems after Hardware Upgrades
There are many possible system failures after a hardware upgrade. The first
thing to check when a system fails to boot is the power and cable connections.
Many times while working inside the case, cables are pulled loose. So, the first
thing to look for is free-hanging cables. However, cable problems will not always
be cables that were not reconnected. Sometimes when a cable is pulled loose, the
user will inadvertently replace the cable incorrectly. The cable may be off one
pin, or a pin may be damaged. Data cables can also be pinched when systems are
reassembled.
Another major problem occurs when mixing different generation
technologies together inside the same PC. When a PC has been upgraded several
times, problems do arise. An older BIOS chip may not be able to recognize certain
new memory module or see the vast new hard drive that has been installed.
Check the system resources for conflicts. (Use the
System Properties
dialog box
or the Microsoft System Information utility.)
Dust Accumulation
The accumulation of dust inside a PC is typical. The type of environment
in which the PC operates, as well as its age, determines how much dust has
accumulated. Large amounts of dust can cause heating problems by blocking
air filters and by collecting on processor heat-sink fins and fan components
preventing the proper dissipation of heat. The dust acts like an insulator and
holds the heat to the CPU rather than allowing the cooling fins to dissipate it. The
dust can clog air filters and render a fan inoperable.
Remove dust carefully using a can of compressed air or a special vacuum
cleaner designed for PC cleaning. Standard vacuum cleaners can generate a
tremendous amount of static electricity, which is very dangerous to computer
chips. Use only vacuum cleaners made specifically for electronic equipment.
Removing dust from a CRT can be dangerous. Do not
attempt to open and remove dust from inside a CRT
without special training. There are dangerous voltage
levels inside a CRT case that remain even after the CRT
has been disconnected from electrical power.
Recovering from System Startup Failure
Recovering from a system startup failure requires the technician to have
advanced skills. Many of the utilities described in this section should not be used
by the inexperienced user because they can cause additional problems if not used
correctly. To become an experienced technician, you should practice using these
utilities in the lab before attempting to use them on a customer’s PC. You can also
download extensive information about each of the utilities from the Microsoft
Support Web site.
Warning
!