Just curious if this has been followed up on by anyone. I just put together an EVGA 680i motherboard, E6300, 2GB Corsair, and a single XFX 7900GS. I had the same issue as the original poster.
I booted and installed everything with the D-Sub cable on an old monitor with no problems. Once I booted on my LCD with the DVI connector, I got no signal on-screen until windows was actually booted. It seems like a BIOS issue to me as well, just curious if there is anymore insight into this issue.
Thanks a bunch!!!