I put in a 575 motherboard in my CC. I did no other modifications. I wanted to make sure the board was ok. It chimed, and I got a grey screen - which was good but the hard drive spins up then spins down after a few seconds and won't spin back up and I get the blinking question mark. I put the stock mobo in with the same result.

Any ideas? I don't have any boot disks right now - at least for a few days. I had 7.1 on the internal 80mb drive.