Hi Thomas
I would be also very happy if I could use my GTX670-DC2T-2GD5 with new UEFI and GOP support, my bios is GTX670 VB Ver. 80.04.19.00.AS03 Latest from asus site
http://www.asus.com/Graphics_Cards/GTX670DC2T2GD5/#support80.04.19.00.2B (P2004-0005) (GPU-Z INFO). I'm ready for testing and got no fear.
🙂In fact I'm already using Ultra Fast Boot in Win 8 on my ASrock Z68E4G3 with beta UEFI 2.31a, Intel i5 2500k HD3000 onboard GPU, GPT formatted SDD and all works great but obviously I cannot use my GTX670 with Ultra Fast Boot.
For testing i got my monitor plugged in with DVI to GTX670 and with DP to Intel HD3000, so for everyday use I boot my Win 7 with Fast Boot enabled (In my case it's monstrously slow, Intel RAID OROM, LSI RAID OROM loading - 1 minute or worse) but when I want to work with Win 8 - I just start "Restart to Uefi" ASrock app in Win 7, then change Fast Boot to Ultra Fast Boot, Onboard GPU to Descrete, save and restart my PC, change input source in my monitor and after few seconds magically Win 8 boots.
😉 So in my case it's Win 7 - 1:45 min loading vs. Win 8 - 0:12 min loading, same hardware with 2SSD, 2RAID0 and many HDDs and additional hardware.