I just rebuilt my PC with a GA-Z77X-UD4H, a core i5-3570K CPU, 16GB of DDF3-1600 RAM, and a Radeon R7770 video card.
The first time I powered on the system I got no video out. Diagnostic code at AE (boot to legacy OS)
2nd time I pulled out the video card and went with onboard video, still no video. Diag at AE
3rd time I pulled _everything_ except the CPU and RAM, still no video. Diag at AE
4th time I tried a VGA cable instead of DVI, still no video. Diag at AE
5th time I reset the BIOS to defaults and video came up with the warning about being rest to defaults. I went in and selected "load optimized defaults"
6th reboot, no video so I reset BIOS back to defaults
7th reboot, just set my legacy boot options and powered down. Added my SSD and got into my OS (Win8)
many more reboots, some worked, some didn't. I had to reset my BIOS back to default to get any video again. I decided to flash the latest beta BIOS (there is only the one production build I was using and two betas there) and now I can't get video back no matter what I try and the diag code is A6 (init SCSI devices of which I have none).
Just now tried a different monitor and RAM, same issue.
Any thoughts?