Last week, I rebooted my machine, and it went wacky. The power light and CPU fan stayed on but no further booting took place. I unplugged the machine, plugged it back in, and the light/fan remained on.. The only way to shut it off, is to unplug it and leave it unplugged. It will not shut down, and it will not boot. I swapped out the power supply, in hopes it was a short, but the new one did the same thing. I checked the power button, and it does seem to have a loose connection, but was not the problem. I took out the ram (ddr pc2700 256) and blew out dust, replaced it with no results. Then I reset the CMOS.. switched the ram to the other slot, and now it beeps at me.. a long beep.. pause.. long beep.. pause. If I remove the ram, it powers up but no beep.
I would like to hear other opinions, but what I have read so far on this forum, leads me to believe that the problem is either bad ram, or the video card.. but the VC on my machine is integrated, so my question for the moment is this....

Is there any way to disable an onboard video card and replace it with a seperate card, if your machine will not boot up?

thank you for any help you can offer... I am at wits end.

This sounds like a motherboard fault and nothing whatsoever to do with the RAM or the video. It could be that there is not enough power reaching the board but as you have tried two PSU's it would look to be possibly a connection actually in the motherboard power connector itself. Swap out the board for a new one and see what happens. i'm initially ruling out RAM and Video adapters at this stage.