Restarts and instability

[Olen]

I've been having an irritating problem with a computer restarting without warning. It can happen at any time but always happens if there is heavy load. When it happens the screen just goes blank then the bios page shows up. When windows loads it says is has recovered from a serious error.

I've tried a few things:

prime95 won't run stable at all (the answers the computer gives can be very wrong).

Squaring a number repeatedly using calculator causes a crash after about a minute.

I wrote a small stress test programme aimed not to test the memory much and it crashed after several minutes (it crashed at a time which would have used most (though still very little) memory).

I couldn't make it load Linux off the cd in anything other than command line mode.


Occasionally windows explorer goes a little before the restart.

Its not the memory as I moved it into my other computer and everything was fine. I also tried putting 256mb of good memory into the broken computer and it would still restart though less readily. It had had 512.

So basically whats wrong? The problem has come on in the last week or so and nothing has been changed during that time as far as I know. It runs much slower than it used to - probably due to the instability.

It has:
AthlonXP 2000
512 Mb memory
GeForce2 MX200 32MB graphics
ASRock K7s41 mobo

Windows XP service pack 2.

The voltages look ok, the CPU runs a little hot (62*C) but is rated for 90*C so should be ok. The northbridge gets hot (I'd guess around 50 or so) but has no sensor...

[doesi87]

My first guess would be that there is not enough power. The computer needs much more energy when it runs under full load so the PSU could be the problem. But then you said you didn't change the hardware components. Have you used anti virus and spyware software to check for unwanted programs?

[slytherock]

I second that. Blame it on the PSU

[Olen]

Yea its running Norton joy of joys (when I said my computer I meant the home one not the one I actually use)... And yes I have tried disabling it to see if it is the problem. But no, no viruses etc unless norton has failed to find them.

PSU - I just checked and nope its not that. I have a spare 600w one lying around so I hooked that up to it which is WAY more than it needs. Still unstable and still crashing under heavy load.

I'm begining to suspect the northbridge or CPU but I don't see why. The northbridge does get hot... but I wouldn't say hot enough to damage it...

Any more thoughts?

[doesi87]

Sorry dude I'm not this much of an expert about this. Just an idea: It may be a software problem. There are strange problems with windows. You could copy an image of your HDD with BartPE to an USBDrive and then install a fresh XP. When it works fine you know its an software problem, if it does not work fine you can roll back the image and use your old XP with everything you installed. About 2 and a half hour work I guess. Or simply wait till some of the cracks around give a statement, maybe less unnecessary work.

[Olen]

Ok its definately not software.

Rather than do as doesi suggested I replaced the HDD in it with one from an old computer running 98. Same problem and one that I didn't have with the computer which the HDD came out of.

So its definately hardware, not the ram, HDD or PSU... Not looking good. Any suggestions?

[Eclecticos]

Move the one Memory stick to the second RAM slot, furthest from the processor. Put a 80mm fan on the northbridge.
If you computer turns on without Pushing the power button, make sure your mobo is spaced away from the mounting panel.

[Greco101]

Could be capacitor related. Check them for bulging and/or leaking. They can also go bad without any signs at all. You may need a new motherboard.

Same thing happened to me except it didn't necessarily have to be under a load to do it... just whenever it pleased.

[Olen]

Cheers again. But again no joy.

Moved the RAM and left the side of the case off which keeps things a bit cooler and the problem was exactly the same.

Can't see anything wrong with the caps but then not all of them are very seeable.

How do you check to see if its mobo or processor without removing the processor to test elsewhere? Is it possible?

Thanks,

[XcOM]

if you can, try sandra soft, it can do tests on one single part of your system.

[rendermandan]

sounds like motherboard to me. I had the same kind of problems too. -Haven't we all at one time? The caps on the mboard go bad over time, and based on your system specs Id suggest upgrading the motherboard and processor. Not to mention the video card.

[Olen]

I can't ever make sandra work and on a computer which locks up the whole time there wasn't a hope so no joy there.

Don't need a higher spec system. All it does is internet browsing, word processing and CAD all of which it did fine. I might try to move a new processor in (I have another). Any hints on applying thermal compound (I don't want to fry anything)?

[doesi87]

Apply it in a thin layer, but cover the whole die. You should get something like this but with a smooth surface and thermal compound on the whole die. (Guess you will use a processor without headspreader)

http://i195.photobucket.com/albums/z294/doesi87/271396541_9eeb9dfeb8Small.jpg

[.Maleficus.]

Use a small dab. For the older Athlons without a heatspreader, you should use ~the size of half a grain of rice. Maybe even less. Then, what I normally do, is to not spread it, put on the heatsink, and rotate it 1 or 2 degrees left and right. It gets out trapped air bubbles, and the heat from the processor will spread it for you.


Edit: And look around the socket and CPU and see if you see some burn or scorch marks. If you do, you know where your problem is.

[Olen]

cheers I got it sorted a couple of days ago.

It was the processor, I put mine in (also socket a...) and it ran fine. Went down to the local computer shop and they gave me two for free :). So its all good. Was no sign of damage to the cpu but that computer is evil and not to be trusted. Apparently thats its third cpu the other two also having died and its onto its second mobo and second set of ram. Persumably something is damaged (last mobos voltage regulator I'd guess) but not my problem.

So alls good (well it isn't but thats another post (sigh)).