Can anyone help me out here? I have this old computer, which has operated fine until two days ago. All of a sudden, it desides to reboot, seemingly at random time intervals. Sometimes, it reboots twice in 10 minutes, sometimes, it doesn't reboot for 3 hours.

For now, it reboots only when I'm not using the computer, but since I hardly use the computer (it's configured as a gateway), that's not really surprising. As far as I can tell, nothing warns for the upcoming reboot: it's almost as if someone presses the reset-botton on the case.

Up till now, I checked all connectors in- and outside of the case. I even checked wether the power- and resetbutton were stuck in any way: not so. I checked to see if all cards were firmly in their sockets, I checked wether the memory modules were in place, everything seemed to check out okay.

Software maybe? I checked everything I could think of, and ended up installing a complete new Operating System (from Windows to RedHat) - the entire drive is repartitioned... So I guess that rules out a softwareproblem... I'm at a loss here, someone, help me out.