PC power on - start, stop, start, stop, etc - eventually powers up

Hi all,

I have a problem that has only recently started (to my knowledge) and I
can't seem to solve it. I've got a P4 3.0GHz PC with an Asis P4P800S-X
board, 512mb RAM, Thermaltake 430W PSU and geforece fx5200 graphics. The
problem is that once the system is warm (and sometimes even from cold) a
shutdown then start gets the computer spinning its fans, powering off,
spinning fans, powering off, and repeating this cycle from 1-10+ times
before actually POSTing. Once it POSTs, it's all fine. Sometimes the
brief power ons result in the drives starting to power up as well, but
usually not. I've flashed the motherboard, replaced the PSU, cleaned and
reattached the HSF, and tried it with only CPU, GPU, RAM, and Video
attached to the motherboard without success in solving this issue. I've
come accross other accounts of similar issues, but they've usually been
solved by the steps I've already taken. Any ideas on where I could go
from here?

TIA,

Ari

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