PC restarts automatically for no real reason

Hi,My pc either does not boot at all despite pressing the power button or if boots once then it goes into a cycle where is restarts itself for no apparent reason what so ever. I have Fedora 14 installed on it and it is the only OS. It has been troubling me for the last 1 month or so, otherwise it was working well and I used to work on my pc for hours on end. There is no virus problem as such. All the other parts have been checked with other pc such as the hard disk, CD Drive, RAM, CPU, power supply and even the monitor. But I am still no where near the real cause as to why it happens. Please guide me. Thanks.

How old is your mobo??

I guess the Power is fluctuating here. I had a similar issue years back, and it got fixed by changing the PSU.

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On second thoughts....or frankly, on reading ur complete post, i see that u checked ur PSU. R u sure changing the PSU isnt helping? Not even changing the RAM?

Hi,My pc and the motherboard are both hardly 18 months old. The pc was lying unused for almost a year until I started using it daily a few months back. To me it also looks like that the power supply is the culprit, but when I used the same power supply in another pc it worked well for more than a day. But it is only 230 Watts, is it an issue here? How much a good power supply costs generally? Thanks.

In another PC where u tried ur existing power supply, might actually require less power, than ur PC. I m just guessing though.But the problem is very deja vu for me.......i had this issue & it got rectified with change of PSU. A good one shud cost u around 800-1k bucks, IINM.

to me its like an issue with your CMOS battery.

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is your date time getting reset??

The CMOS battery is just 2 weeks old. I am not a gamer or into designing heavy duty stuff such as animation or graphics. I just do some basic programming and use Linux - Fedora 14, Ubuntu 11.04, Debian etc. I have only 1GB DDR2 RAM but I am ok with it.

Sometimes when it restarts there is American Megatrends screen and there is a message on this screen which goes like...


Warning ! over clock fail

I have never changed anything in the BIOS and I have never even dreamed of over-clocking if this is what this error message means. I do not even know how to overclock. The motherboard is Biostar G31-M7 TE and BIOS is from AMIBIOS ie American Megatrends.

Thanks.

your Bios settings have somehow gone bad, hit f2 at boot to load defaults if that does not work hit DEL to go in BIOS settings , restore to default , commit and save them, remove the CMOS battery for few secs to remove and clear old cache , otherwise your bios is gone would be better to get a hardware guy to come around then.

along with other's suggestions, try doing a memory test to see if your PC's RAM is perfect and hasn't got bad cells. I think memory test will be one of the boot options. Also, it should be available as a boot option in your distro CD

Get some CPU monitoring utility for Fedora, I think it's CPU overheating.