Hmmm.

Okay, I bought a new power supply, before I even tested the existing one. My reasoning: Even if the problem was with the motherboard or the CPU, I would never trust the existing power supply, thinking that it might have caused the other components to fail. So I was going to have to spend money on the power supply no matter where the fault was.

The new power supply did not allow the motherboard to boot. Same symptoms.

I finally took the board out of the case and had a close look. Two large capacitors on the motherboard, near the CPU, appear to have "swollen" tops. I don't think they're supposed to be that way. I think that's what happened: those caps blew.

Anyone have any experience with this sort of thing? Would replacing those caps fix anything?

The motherboard, by the way, is this one. If you look at this picture...

...the capacitors that blew are the pair located just below and to the right of the purple LPT1 connector.

Update: Here is a bigger picture of the board. The caps that blew are to the right of the purple LPT1 connector in this photo.

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Tony Fabris