PC Hardware A Beginner’s Guide

Chapter 24: Troubleshooting PC Hardware^627

If the processor is Pentium-class and does not have a heat sink or a cooling fan, it is

definitely overheating. A heat sink and fan, which typically come as a single add-on unit,

should be attached using liberal amounts of thermal paste (aka thermal glue).

To troubleshoot the processor, heat sink, and fan, use the following steps:

1. Examine the processor’s heat sink and fan to verify that they are installed
   properly and are not cracked or broken.


2. After making sure the heat sink is not hot, attempt to move it slightly back and
   forth to check for looseness. If it is loose, it may not have the proper seal between
   the heat sink and fan. Follow the directions of the manufacturer to seal the heat
   sink and fan to the processor.


3. Remove the heat sink and fan (it typically unclips from the top of the processor)
   and verify that the processor is properly secured in its socket or slot. If a ZIF
   (zero insertion force) socket is in use, make sure that the ZIF arm is locked and
   anchored. Reseat a Slot 1 or Slot A processor package. Reattach the heat sink
   and fan, making sure it is attached securely and properly.


4. Make sure that all of the unused expansion slots on the back of the PC’s case
   are filled with slot covers.

System Clock Jumpers

If the PC has symptoms of overheating but everything seems to be in order, the problem

could be that the system clock jumpers located on the motherboard or the CMOS set-

tings for the system timers are not set correctly for the processor. This would cause the

processor and motherboard to use different clock rates and timings, which would be-

come more out of sync as the system ran and eventually would cause a system failure.

Check your motherboard and processor documentation for the proper clock settings

and adjust them accordingly.

Processor Power Problems

If the POST process is signaling a processor fault, another problem could be that the proces-

sor is not getting the proper power it needs. Use a multimeter to check the power connection

to the motherboard. If any of the leads are low (according to the motherboard’s documenta-

tion) or dead, the power supply should be replaced. Otherwise, you may have a dead pro-

cessor or a bad socket or slot mounting, which would require replacing the motherboard or

the processor itself. If you install a new processor and it fails to solve the problem, the prob-

lem is isolated to the motherboard.

Troubleshooting the Floppy Disk Drive

Troubleshooting a floppy disk drive is essentially pinpointing that the floppy disk drive

is the source of a problem, and if so, replacing it.