Very odd problem here - can you think of an explanation??

[eUphoria]

Its a strange thing - turn PC on - nothing, no vga signal or post etc. I've tried rebuilding it, checking connections etc etc. If i leave it in this state for few minutes (PSU on, fans turning, pump running for WC) then press reset it boots absolutely fine no problems at all from then on. Strange i thought!!! Itsa little annoying, can anyone come up with an explanation for this??

[killie99]

Suspect it's the power supply - capacitors are chuffed and therefore the supply can't hold the votage to the correct level, after a bit the caps manage to retain enough charge.

[finnrogers]

Have you distributed the components onto different 12V rails of your PSU? 7800GT powered properely? If you have no VGA signal at first this could be a clue. Otherwise I would concurr with killie99 above

[kalniel]

Its a strange thing - turn PC on - nothing, no vga signal or post etc. I've tried rebuilding it, checking connections etc etc. If i leave it in this state for few minutes (PSU on, fans turning, pump running for WC) then press reset it boots absolutely fine no problems at all from then on. Strange i thought!!! Itsa little annoying, can anyone come up with an explanation for this??

It's called a cold boot problem. You are able to warm boot fine. It can be caused by the PSU not supplying enough power in the standby state, or more simply a BIOS problem - try updating the BIOS first to see if that helps.

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