NP Troubleshooting Guide
Updated 30
May 2002
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Are there any burnt parts or odors? Any loose cable connections?
*
Is the computer plugged in?
* Are all switches turned on? Computer? Monitor? Surge protector? UPS?
Separate circuit breaker?
*
Is the wall outlet (or surge protector) good?
* If the fan is not running,
turn off the computer, open the case, and check the connections to the power
supply. Are they secure? Are all cards securely seated?
*
Check the voltage output from the power supply.
* Remove all nonessential
expansion cards (Modem, sound card, mouse) one at a time. Verify that they are
not drawing too much power and pulling the system down.
* It is possible that the
expansion cards are all good, but the power supply is not capable of supplying
enough current for all the add-on cards.
* It may be that there are
too many cards and the computer is overheating.
* Excessive dust insulates
components and causes them to overheat. Vacuum the entire unit, especially the
power supply's fan vent.
* Trade the power supply for
one you know is good. Be certain to follow the black-to-black rule when
attaching the AT power cords to the systemboard.
* Is there strong magnetic or
electrical interference? Sometimes an old monitor will emit too much static and
EMF (electromagnetic force) and bring a whole system down.
* If the fan is running,
reseat or trade the CPU, BIOS, or RAM. A POST code diagnostic card is a great
help at this point.
* Sometimes a dead computer
can be fixed by simply disassembling it and reseating cables, adapter cards,
socketed chips, and SIMMs. Bad connections and corrosion are common problems.
* Check jumpers, DIP
switches, and CMOS settings.
* Is the system in a Doze or
Sleep mode? Many "green" systems can be programmed through CMOS to
suspend the monitor or even the drive if the keyboard and/ or CPU has been
inactive for a few minutes. Pressing any key will usually resume exactly where
the user left off.
* If the battery is dead, or
dying, it may cause problems. Sometimes, after a long holiday, a weak battery
will cause the CMOS to forget its configuration.
* Use a POST code diagnostic card to check
systemboard components.
*
Exchange the systemboard.
The computer
does not recognize all installed RAMs (memory modules)
*
Are CMOS settings correct?
*
Run a diagnostic software such as PC Technician to test memory.
*
Are RAM or SIMM modules properly seated?
* Look for bent pins, or
chips installed the wrong way, on cache memory. Look for loose memory modules.
* Place your fingers on the
individual chips. Sometimes a bad chip will be noticeably hotter than the other
chips.
* Make sure the RAMs have
the correct or consistent part number. For example, if there are four installed
RAMs, they usually must be the same size (in megabytes) and same speed (in
nanoseconds).
* Reseat the RAM (memory)
modules.
* Trade RAMs one at a time.
For example, if the system only recognize 6 out of 8 megabytes of RAM, swap the
last two memory modules. Did the amount of recognized RAM change?
* Use memory modules with
the same part number.
* A trace on the systemboard
may be bad. If this is the case, you may have to replace the entire
systemboard.
Error
messages appear during booting
* When a PC boots, one beep
after POST indicates that all is well. If you hear more than one beep, there
may be an error.
* If error messages appear
on the screen, then video is working. Look up the error message and check the
that part. (e.g. If the message "Primary master HDD fail" then you
have check HDD for that error)
* If a problem arises during
a soft boot, try a hard boot. A soft boot may not work because TSRs are not
always "kicked out" of RAM with a soft boot, or an ISA bus may not be
initialized correctly.
* Boot from a floppy disk.
You should boot to an A prompt. If you are successful, the problem is in the
hard drive subsystem and/ or the software on the drive.
* Can you access the hard
drive from the A prompt?
* If you can get a C prompt,
then the problem is in the software that is used on the hard drive to boot,
such as the partition table, master boot record, operating system hidden files,
or command interface files. See the suggestions for hard drive problems.
* Run diagnostic software
(PC Technician or McAfee Utilities) to test for hard drive hardware problems.
* Check all connections, and
reseat all boards.
* Reduce the system to
essentials. Remove any unnecessary hardware such as expansion cards, and then
try to boot again.
Windows
95 does not load correctly
* Boot into Safe mode and
then try booting normally. While in Safe Mode, if any changes were made in
Control Panel just before the problems occurred, undo the changes.
* Try booting from the
McAfee Utilities rescue disk.
Problems
after the computer boots
* If you suspect that
software may be the source of the problem, try diagnostic software such as
McAfee Utilities Disk Tune or ScanDisk before reloading the software package.
* Suspect the applications
software using the device. Try another application or reinstall the software.
* If you suspect that
hardware is the source of the problem, first isolate the problem by removing
devices and trading good components for suspected bad ones, one at a time. Be
aware that the problem may be a resource conflict.
* Check the voltage output
from the power supply with a multimeter.
* Check jumpers, DIP
switches, and CMOS settings for the devices.
Suspect
a corrupted device driver. Reinstall the driver
