Brian Cloutier wrote:

I have a friends PC at my house to check out. It would not boot, no
activity, (Power supply fan not turning) no post no nothing. I had
a 235 watt power supply laying around and replaced the 250 watt that
was in the PC. The 235 I put in powers up but still no post, no
beeps, no nothing. Is it possible that the 235 is not enough watts?
I also disconnected the 2 cd drives and just left the HD and floppy
connected, still no post or beeps.

Maybe the first PSU fried because the mobo became bad (capacitors
leaked or bulged -- see www.motherboardrepair.com) or shorted against
the case. PSUs in major brand computers are normally really high
quality and can't be damaged by the mobo, but eMachines seems to be an
exception and sometimes uses even Powmax PSUs, which are among the
worst.

If the HD spun up, it probably means that the +12V and +5.0V rails are
OK, so that leaves the +3.3V rail in question, but I have a feeling
that it's OK, too, although I had a cheapo PSU where only it failed
(when a memory module plugged in backwards). A voltage meter will tell
you for sure, and even the cheapest digital one (not analog) is very
accurate.

That 235W PSU is probably powerful enough, at least for testing the
mobo without any CD or hard drives connected, unless it's a realy bad
brand. What brand is it, anyway?