"Chris" said:
I have an ASUS P4B. Been working fine until a couple of weeks ago. Started
with not waking up to mouse or keyboard. Now when I boot I usually get no
P4B splash or text. Bios menu when I can get to it is very slow. XP always
boots fine (no video until XP starts) and works as good as XP can. Linux
boots but with no video most of the time. When I can get video its in
failsafe. It boots because I can login and shutdown without seeing what I
am doing. startx X no video but you can hear the monitor reset. A dos boot
disk will mostly boot to a blank screen. I was able to flash the bios to
the latest 1012. I check Bios settings and quick boot is disabled. Wake on
space bar and PS2 is enabled. No alarms in ASUS MB monitor. Is the mother
board dying or am I missing something. Computer runs 24X7 for two years no
problems then this starts. Since video works fine in XP I assume thats
good. Any suggestions or is it dying. Thanks in advance.
With that set of symptoms, it is hard to identify one component that
could cause all the symptoms.
The power supply is the least reliable item in a computer these days.
When you get into the BIOS, go to the hardware monitor page, and
check that 3.3, 5.0, 12V voltages listed are within 5% of their
intended values. But, in your case, about the only thing that looks
power supply related, is perhaps your "failure to wake" symptoms,
which could be caused by a weak +5VSB standby voltage.
It could be the video card is dying and some modes don't work as
well as others. But, you would expect to see some kind of abnormality
in WinXP if that were the case. Can you run a heavy 3D load, like
3DMark or a 3D game, and does the computer survive such a test ?
That might identify whether it is the video card or not.
Motherboards generally have some number of voltage conversion circuits
on them, and if one of those is failing, that is another root
cause to consider. The DIMMs can have their own regulator, the
AGP I/O voltage comes from some kind of regulator etc. Again, I
don't see one of those by itself, causing your symptoms.
The slow operation in the BIOS, could be that the L1/L2 cache are
not enabled. Or, the computer could be getting an "interrupt storm"
from some dying hardware (interrupt signal shows up, processor
attempts to service it, exits interrupt handler, and interrupt signal
is there again - for example, some people are seeing symptoms like
that with the Promise 20378 RAID controller used on many modern
Asus boards right now).
Things you can try, as you've flashed the BIOS already:
1) Unplug the computer and clear the CMOS. Usually, the manual will
have a procedure involving the CLRCMOS jumper. Unplugging the
computer prevents +5VSB from damaging the board, when using the
CLRCMOS jumper.
2) Enter the BIOS and do "Load Setup Defaults". This ensures the
data structure holding the BIOS settings, is refreshed and matches
the new BIOS. Write down any custom settings you have made on a
piece of paper before doing this, as you'll have to put them
back after a "Load Setup Defaults".
3) Next step, swap video card for another.
4) Next step, swap power supply (may cure wake up problem at least).
5) Test other components from the computer on another system.
HTH,
Paul
