to make because the SCSI is usually a higher performance disk drive. If the PC’s BIOS
doesn’t allow a SCSI drive to be the boot disk, check with the BIOS manufacturer for an
upgrade that will allow this configuration.Troubleshooting Memory
Typically, three general types of memory (RAM) problems on a PC require troubleshoot-
ing, and for the most part, these problems happen just after new memory has been in-
stalled. See Chapter 7 for general information on memory systems. Memory problems also
occur because of electrical problems on the motherboard or, on older systems that use DIP
(dual inline packaging) memory, chi pcree pcan be a problem. Troubleshooting memory
problems is complicated because many FRMs give out symptoms that appear to be mem-
ory problems. If you’re having memory problems, you should check the following: Configuration If you have just added new or additional memory to a PC, the
amount of memory installed may be more than the PC or operating system is
able to support or the BIOS CMOS settings may be incorrect.
Hardware All of the memory installed must be compatible and installed in
complete banks. If slower memory is installed in one bank, all of the memory
will operate at the slower speed. The problem could also be that at least one
memory module or chip is defective.
Installation Most memory problems are caused by the memory chips or
modules not being completely or properly seated in their sockets. It could
be that a socket is bad, has a bent or broken lead, or just needs cleaning.Identifying a Memory Problem
Knowing when a memory problem happens is very valuable information. A memory
problem that happens during startup is a much different problem than one that happens
while an application is running and each is resolved quite differently. Memory problems
can occur in these situations: The first time a new PC is started This common problem is caused by the
rigors of shipping a PC. The memory chips may need to be reseated or may
be missing. A problem that appears to be memory-related could also be a bad
motherboard. Check with the manufacturer or the vendor.
Immediately after new memory is installed Check the part numbers and speed
of both the new and the old memory modules. Verify the memory was properly
installed or configured in memory banks. If DIP or SIMM (Single Inline Memory
Module) memory is in use, check that each bank is filled before memory is placed
in another bank. You should also verify that the memory is appropriate for the
motherboard, chipset, and processor. For example, the memory bus on a Pentium
III PC is usually PC133-compliant, so the memory installed on this system must
be PC133.Chapter 24: Troubleshooting PC Hardware^633