computer components & hardware - What do these symptoms suggest?

"JAD" wrote in message
...

"Doc" wrote in message
nk.net...
You may have seen my other posts problems with a Compaq Deskpro EN
PIII
933, 512 Megs Ram, XP Home.

To briefly recap, this round of problems seemed to start a few days ago
with
an NMI: Parity Check / Memory Parity Error and would thereafter only boot
to
Safe Mode. Wouldn't do a normal boot at all. This had never happened
before.
The computer had run basically flawlessly for some time.

After reinstalling the sound card, video capture card and modem the
computer
seemed fine again. However shortly thereafter it started exhibiting a new
symptom. It would wink out in the middle of doing something. Blank
screen,
computer seemingly dead except for a green power light. Or it would
sometimes freeze. However, the NMI Parity check error hasn't arisen
again.
Don't know if the current symptoms are related or not.

Now, in addition to the freeze/wink out symptom, I've noticed some other
issues:

1) It will only boot intermittently. When it boots normally, you get a
big
red Compaq logo on the screen and the Enter Setup / Network Service Boot
options at the bottom. Now, it will get as far as showing the Compaq logo
but just hangs there. Sometimes letting it sit for a while or unplugging
it
from power, waiting a minute and replugging seems to let it boot.

2) However, even when it boots, it won't allow me to go into Bios
(setup).
Looks like it's starting to, but then just goes to a normal boot. Per the
suggestion of a poster in another thread, I tried removing the battery
and
putting it back in, which temporarily lets me get back into Bios/Setup,
but
thereafter begins displaying the same symptoms. Won't let me into
Bios/Setup, just goes to a normal boot. I tried removing the battery a
couple of times, and both times it allows me into Bios but only once.
Once
booted, "Standby" mode seems to work okay and a couple of programs I
tried - Windows Media Player etc. seem to work but I haven't run it hard.
However, after shutting down, it may or may not successfully reboot as
per
above.

3) No longer sends a video signal through the nVidia GeForce2 MX400 video
card which had been working flawlessly up to now. The first few times it
was
intermittent - sometimes it would, sometimes it wouldn't, now I only get
video through the onboard video port. Tried reinstalling the drivers for
the
card, doesn't seem to make a difference. Oddly, I also don't find it
listed
in the Add/Remove Programs list in control panel.

I think I've eliminated the RAM as the culprit. Since the Compaq wouldn't
recognize Memtest or the Microsoft Memory Diagnostic in either the A: or
CD
drive, I took the Ram out and put it in another PIII (the one I'm writing
on) and ran the diagnostics. Well, 2 of the three modules. This IBM PIII
won't accept the single 256K module. The 128meg modules test out as okay,
as
well as simply exhibiting no problems in running the computer.

Putting only those two 128meg modules back into the Compaq, it still
generates the same symptoms above.

Sincere thanks for any input.

I would be looking to the Mainboard or the PSU. A quick look at the
mainboards capacitors(gray cylinders) to check for bulging or leaking. (if
your an old guy like me then I would use a magnifying glass or glasses.)
PSU, well that's a toughie as a multimeter could help but its hard to
test
with a load, so a spare or a new one to test with is an easier way.

Did you go into BIOS and set to boot from floppy, then CD then HD?
Mike.