I have had a problem with spontaneous reboots for a while now. First it began while I was in WinXP, so I thought it was a problem with the system so i formatted the disk and installed Redhat, but that did not go well because the problem continued. The restarts does not go cleanly which means that it breaks files that are open, so a few restarts and the system is broken.

I talket to some people and they said that its probably the PSU or suspect ram, now I have upgraded my PSU and changed my ram, still the computer restarts for no obvious reason.

Does anyone have a tip.

Generally they're right; PSU overload/instability and faulty memory would be my first two thoughts. My next thought is overheating. What are the temperatures like in your case and on your CPU? Can you install another fan or two to try to cool it down in there?

Btw, is all the old RAM gone?

The temperature is about 40C on the cpu and 36C in the case.

My system specs are:
PIII Coppermine 866MHz
MSI ms-6309 mobo
Pci 128 soundcard
Hauppauge WinTV card
ISA 10MBit Ethernet card
The ram is now taken from a stable computer.
pc100 64Mb
pc100 32Mb
Western seagate 80Gb
IBM 10Gb

I have checked the syslogs and here they come.

Aug 19 07:01:00 ba2056b CROND[1807]: (root) CMD (nice -n 19 run-parts /etc/cron
Aug 19 08:01:00 ba2056b CROND[1826]: (root) CMD (nice -n 19 run-parts /etc/cron
Aug 19 09:01:00 ba2056b CROND[1841]: (root) CMD (nice -n 19 run-parts /etc/cron
Aug 19 09:13:41 ba2056b syslogd 1.4.1: restart.

Well those temps are perfectly normal... Unless your CPU is under a lot of load when it reboots then I guess you can pretty much rule heat out...

You'll probably want to wait for more opinions, but it might be time to boil the computer down to essential components and troubleshoot that way. btw, you probably don't have a spare Socket 370 CPU lying around, do you?

Actually I just though to this, it's possible that your motherboard is improperly screwed into the case. I've seen that happen before. The best way to check for this is really just to take out all the screws, line the board up, and re-mount it carefully, being sure that all the screws are not outside of their marked spaces and that nothing conductive is touching the back of your motherboard. Hopefully this is practical for you. :/

The computer can restart when its on light load so that should not be a problem. I have tried to remove everything except the graphics. Still it reboots. Ill check in to the mobo fastening.

And sorry I dont have a socked 370 processor lying around.

As I said, ill turn off the computer and se if the mobo is mounted incorrectly.

The mobo wasn´t mounted correctly because one screw was not attached, it is now but we will just have to wait and see, if it reboots again.

Well generally when this is the problem what you will find is that a screw partially overlaps a circuit, but there are still a number of things that can be cleared up by that process even if you didn't observer such overlap.

If it's not, then that doens't leave much else... :/

Well, good luck.

Sorry that did not help! It rebooted 3 times yesterday destroying some of my open files.