I have this exact issue, 5A BIOS on Ga-990FXA-UD3, flashed using @BIOS (hey Gigabyte - if we're not supposed to use it, DON'T PROVIDE IT ON YOUR SITE), now I get "Loading Operating System" - and even though my DVD-drive shows up, I can't boot from it even if I hit F12 and select it.
So my problem...I can't get qFlash to detect my USB stick...? I flashed it as FAT32 and put the BIOS in the root directory, legacy USB is enabled...any ideas?
What is the point in having DUAL BIOS if the user can't manually select to use the other BIOS?