Instant rebooting

Hi all,

I've got this really nice MSI motherboard, from friend. It's got just a small problem. When Windows 98 SE 4.10.2222A is started, and jumps to idle (when nothing is left to do), the core voltage will start to have fluctuations. (from about 2.09V to 2.15V). When it does this, the computer wel reboot spontanuesly within a minute, without any forgoing warning of any kind. It seems to be a problem with windows' idle signal (neither dos nor linux nor sunOs gives this problem). Does anyone have a solution for me? I've already considered and done: Bios flash, APM settings, manual/auto core voltage, diffirent proc, new strips of mem and i tried something with pagefiles (idea from a friend of mine). Any help would be apreciated. And sorry for my english, it stinks at some points ^^

Thanks in advance,
crashmatrix

 

Have your checked the temperature of the processor, chipset and video card? I ask this because overheating of either one will force a sudden reboot. Everest can monitor them, and much more.
Have you installed the motherboard drivers for windows as the very first thing?