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PC reboots: Hardware problem possibilities

Hello all,

I have an IBM NetVista 2257 (2001 model) Pentium III 1GHz based machine. It started behaving rather strangely in the last three weeks as it rebooted all of a sudden(a few times in a week) without a warning. It runs WinXP Pro, fully patched.

A few days ago, when it rebooted a few times before it even finished starting Windows I got annoyed and tried to find the cause. Here is my take:

  1. Power supply: Works, because I was able to run memtest for 97hrs straight! (wasn't home to stop it)

  1. Hard disk: It does not seem to be the cause. While booting from a Knoppix Live CD it still reboots before it finishes the boot process.

  2. Memory: memtest gives me error. But then it gives me the exact same error with both or either one of the two memory modules installed. I checked with memory(2modules) from a working machine, and it gave me exact same error. Still reboots with the memory module from the working machine. So _it seems_ the RAM is not at fault here.

  1. BIOS battery is good too.

The inside of the computer is surprisingly clean and very less likely that dust has anything to do with it (blocking fans or DIMM connectors).

The only other reason that comes to my mind is that several of the electrolytic capacitors on the motherboard are either bulging or electrolyte has leaked out a bit.

Is there anything else I should be looking for? Any other reason that the computer is rebooting? Did I miss anything while debugging the possible cause for the problem?

Thanks in advance for the help, /kds

Reply to
BW
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Bulging caps, particularly round the CPU, is a known problem for this sort of behaviour. If any are actually leaking electrolyte, then you need to get them hooked out, and the board cleaned up pdq, before any tracks and thru' plated holes get attacked. You need a very good iron to remove them. There has been previous posts about this.

Arfa

Reply to
Arfa Daily

99% sure its bad electros. The NetVistas of that era were plagued with the problem. My test PC is, you guessed it, an IBM NetVista 1GHz Celeron that I got for free because of..... bad caps. Caps cost me about $20 + shipping from Digi-Key. Page here on how to remove caps, etc.
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Wayne
Reply to
Wayne

Rebooting is how Windows eliminated the infamous "blue screen of death". Instead, the system reboots.

Look for OS problems before look> Hello all,

Reply to
Mike Berger

I think you missed my original post a little bit. I had written that I tried to boot the machine with a Knoppix Live CD and still got the same rebooting while the hardware was being scanned during the boot process by Linux. This eliminates the possibility of a problem with WinXP(or for that matter the hard disk) which is causing the problem.

Reply to
BW

That website looks like good help. Now comes the difficult part: is there is a way to get a full circuit diagram of the motherboard on the machine? Or do I just go and start to note down the specs of each capacitor on the board?

thanks Wayne, /kds

Reply to
BW

But the OP already said that he'd got bulging and leaking caps ... In order to run Mac or Linux, he'd also have to grow a beard, and buy some sandals !!

Arfa

Reply to
Arfa Daily

Just have a look at the cap values on the board, there are only a handful of different values you will need.

Wayne

Reply to
Wayne

Thanks, Wayne. Will do that and then see if the website you mentioned can provide those.

/kds

Reply to
BW

Digi-Key will have them

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Wayne

Reply to
Wayne

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