What do these symptoms suggest?

[Doc]

You may have seen my other posts re: 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.

 

[JAD]

You may have seen my other posts re: 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.

 

[Doc]

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.

If it's the mobo, this computer is basically hosed?

 

[Jim Land]

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.

Definitely try a known-good PSU. It's just so darn easy to unplug the old
one and plug in a spare. Cross your fingers and hope it's the PSU!

 

[JAD]

If it's the mobo, this computer is basically hosed?

If it were mine and I found out it was the main board I would take out
everything that's good and dump the system. It would be very hard to find a
MB for that, and a NEW board and CPU will most likely need memory and a
different PSU. Along with AGP and PCI going away now, your old hardware
unfortunately may not be practical any longer.

 

[XavierB]

don't bother trying to find a new mobo, it'll cost you the price of a new
system. better to salvage what is working and build a new machine

Xavier

 

[Doc]

You may have seen my other posts re: problems with a Compaq Deskpro EN PIII
933, 512 Megs Ram, XP Home.

Any chance these symptoms could be caused by the OS?

 

[Michael Hawes]

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.

 

[DaveW]

It sounds like your motherboard is failing and a has a thermal fault that
occurs when it's been on. I think you may be facing getting a new computer
since motherboards for that older machine are either unavailable or VERY
expensive.

 

[Ben Myers]

Probably not the OS. Definitely mobo or power supply... Ben Myers

 

[Arno Wagner]

Any chance these symptoms could be caused by the OS?

The OS cannot trigger an NMI. Only hardware can do that.

Arno

 

[Ben Myers]

If you can get the parts for cheap and want to repair it yourself, the computer
is not hosed. It all depends on the color of your money and the amount of time
you have.

The IBM computer probably was incompatible with the higher density 256MB DIMM.

Does your model of DeskPro use a standard ATX power supply with a 20-pin
connector or a proprietary power supply with 24-pin connector? If the former,
you can actually use any standard ATX motherboard in the case, but Windows XP
will throw up on a non-Compaq motherboard. And, of course, the power supply is
standard form factor, if the connector is 20-pin.

I have some DeskPros in my warehouse, some whole, and some in parts. Depending
on the type of power supply and motherboard, I can certainly part out the
computers for short money. Heaven knows, Pentium III computers are not hot
sellers around here... Ben Myers

 

[kony]

It sounds like your motherboard is failing and a has a thermal fault that
occurs when it's been on. I think you may be facing getting a new computer
since motherboards for that older machine are either unavailable or VERY
expensive.

It's not very hard or expensive to find an old socket 370
board... main issue would be whether mATX or full ATX, and
whether the PSU is standard or not. Most from that era were
standard, except some of the slimline, SFF desktops.

 

[Doc]

If you can get the parts for cheap and want to repair it yourself, the computer
is not hosed. It all depends on the color of your money and the amount of time
you have.

The IBM computer probably was incompatible with the higher density 256MB DIMM.

Does your model of DeskPro use a standard ATX power supply with a 20-pin
connector or a proprietary power supply with 24-pin connector? If the former,
you can actually use any standard ATX motherboard in the case, but Windows XP
will throw up on a non-Compaq motherboard. And, of course, the power supply is
standard form factor, if the connector is 20-pin.

This is a 24-pin Compaq Power Supply. Apparently from around 2001.

I have some DeskPros in my warehouse, some whole, and some in parts. Depending
on the type of power supply and motherboard, I can certainly part out the
computers for short money. Heaven knows, Pentium III computers are not hot
sellers around here... Ben Myers

That's a distinct possibility. Do I remove _spam_me_not from the address?

 

[Ben Myers]

Then I am well familiar with the model. I have both power supplies and
motherboards in my warehouse.

To use a more standard motherboard, you would need to change out the power
supply in the chassis.

A non-Compaq motherboard requires minimal changes to the wiring from the
motherboard to the front panel LEDs and on-off switch... Ben