PC does not start

[KAITLIN]

I have a Pentium 4 LGA775 4.34 533 Mhz 1020 Kb under windows XP.
At startup, but the screen remains black, no display of the BIOS. (the blackout came gradually. before that, it displays the bios and hangs, or run Windows XP and crashed. But for several days he does nothing.

I replacement graphics card: no result, replacement motherboard : no result, replace the CPU with a pentium4 LGA775 3.3: no result.

Can you help me ?

Thanks

[jasonR]

The only track that seems likely is a bad isolation of the motherboard or a component, check that no components hits the box by putting the motherboard to ground. Test all the components on another configuration likely to receive to determine which cause the problem.

[Blakeexz]

But it seems to me that the failure is mostly electrical but this can be confirmed by a test shop, hard to do via a forum. It seems that other users have had this problem of contact with the housing component on this model but it remains to be confirmed.