Yes, I've worked the CPU cards in well enough. And it is chiming so I don't think the problem lies there.

Specifically, I'm getting no video signal whatsoever. My display just remains asleep. And there's nothing wrong with the display.

Power on > Chime > Hard drive spin-up > Hard drive activity > No video signal whatsoever

PRAM doesn't take? As in, you do the key combination and it doesn't chime again?

Click to expand...

Bingo.

Tried several times, too...