Two Dead MBs?

Last week I was on my computer when is died like it had suddenly lost power. After that it was unresponsive except for a flicker from the power LED once in a while. I figured it might have been the PSU, so I replaced it, with no luck. My roommate had an old computer that run on the same processor, so I put my drives, my 8x agp graphics card and my wireless/sound cards in it and tested the power. It powered up for a second, and my GPU sparked, so I shut it down and pulled it out.

Running with only the new drives and PCI cards, I tried to boot it, and it gave me the bluescreen that suggests checkdisk. I tried running it without minus one drive at a time which didn't help at all. While I was in BIOS, my monitor went black, and the power LED on my computer died, and he ATX power button wouldn't shut down the power. Now there's no response except for the fans and HD LED turning on, and there is no way to turn it off without cutting the power.

Anyone have any ideas?

 

Did you use your CPU or his?
Your PSU or his?

 

I used both his PSU and CPU, and RAM