PC restarts 0.5s after being turned on, but otherwise works fine

Hi,

As per the title really.. I have a homebuilt PC, with a Gigabyte EP-43-DS3L motherboard, and an E7400. I have noticed lately that sometimes, the computer will turn off within 0.5s of pressing the ON button. It will then wait for another half second, and then proceed to boot to windows and work normally. This happens so fast the bios screen dosent even appear. Once on, everything works perfectly.

In all fairness, I think this began after I overclocked the computer. This never happend at stock settings. FSB is now 333MHz (up from 266MHz), Multipler is now 10x (down from 10.5x), and FSB strap is 2.4B (was 3.0A), Fcpu is now 3.33GHz (up from 2.8GHz).

Any suggestions as to what I can do to rectify this? I am well aware that removing the overlock fixes it! but I would like advice on how to proceed, keeping a similar overlock, seeing that it works fine otherwise. (Reasonable tempertaures, stable etc)

Thanks

It looks like the BIOS is trying to re-set itself because it thinks it's unstable. Also, you OCed via the BIOS right? Also, did you install DES (Dynamic Energy Saver) software that came with the driver DVD?

Yes, the overclock is set via the BIOS. I Have not installed the dynamic energy saver thing, I assumed that it would just add extra drivers and bloat that I would not want; perhaps I am wrong on that front!

I should also add that this seems to have something to do with FSB speed. I have tried a few combinations of overclock settings to asses each one. In my previous attempt, I achieved a similar cpu speed, but using a slightly lower FSB, and using the full 10.5x cpu multipler. I was using a 266MHz strap, and after reading about a bit i found that choosing a lower strap tightens MCH-FSB timings, so I changed the strap to the 333MHz one, and at the same time thought it best to set 333MHz FSB and lower the multipler to get the same overclock. Hoping it would be more stable...

You are actually right in not loading DES. It makes system unstable.

Ahh good good. I assumed that logically without the drivers loaded the board would simply default to using all phases of the CPU regulator to guarantee that it could supply enough current to feed the processor otherwise the thing would likely die before it even got to windows.