I've been running this rig for about a year now. I recently upgraded my card to a EVGA 570GTX (from an EVGA 9800GT) and needed to upgrade my PSU to power it, so I got a Corsair 750W power supply (from a 500W PSU). Now, when I try and start it up, I get no display on my monitor, no response from it at all.
I put the old card back in, and it won't display a picture either. I don't know that it's the PSU, though; the computer starts and all the fans go, even the GPU's fan (stuck my hand inside to feel it... prob not the best idea).
All of my fans start but one, my anterior exhaust fan, which has an odd way of being powered (it leads to the fan controller, where all the power seems to come from).
Any help at all would be appreciated; I was really looking forward to this upgrade.