What GPU are you using on Win10 EFI installation?

[owbp]

I've tried quite a few times to install Win10 with EFI boot and failed miserably with the following error



That was until Squuiid told me that one of my PCIe cards has BIOS. So I removed my MSI R9 280X (the only PCIE cards in my Mac), put back GT120 and I installed Win10 EFI with no problems.
I could even install it with R9 280X in place as long as I used GT120 as my display card. But once I installed the drivers (for both cards) I couldn't boot into it anymore.

So, since then I have tried flashed bios and original UEFI ready bios in my R9 280X and results were the same (blue screen above), Im wondering what card are you using with Win10 EFI?

Are all R9 280(X) problematic, or did I just do something with my ROMs when flashing them for boot screens?

So, to repeat the subject What GPU are you using with your EFI installed Windows on MP4,1/5,1?

 

[Squuiid]

GTX 680 ME, or if you want to run the Mac solely as Windows 10 (no macOS) then a GTX 1080 or 1070 run great also. Ensure the card you get has 2x6pin or 1x8pin power requirements and not more.

 

[ActionableMango]

So, to repeat the subject What GPU are you using with your EFI installed Windows on MP4,1/5,1?

GTX980 w/ MVC flash
On 5,1 with Win10 EFI

 

[owbp]

Ok, two for nVidia.
I really couldn't find any definitive post, but in a few places I've seen that HD7970 are mentioned as incompatible with UEFI booting. On the other side MSI R9 280X has hybrid bios but that doesn't seem to finish the job.
I just have to wait and see if someone is using Tahiti series and if not, then start choosing a nVidia.

Funny thing is that I've always used nVidia GPUs (since Geforce 2 MX) but started buying AMDs (HD6850, HD7950, R9 280X) since I got my first MacPro, haha.
It seems like I cannot run from nVidia!

 

[AidenShaw]

I really couldn't find any definitive post, but in a few places I've seen that HD7970 are mentioned as incompatible with UEFI booting.

Is that really the issue - Windows supports booting from UEFI, and Apple only supports a bastardized version of the old EFI spe?

 

[owbp]

Is that really the issue

Well that was I guess, since I could, without any problem, boot into Windows' "EFI Boot" with stock GT120 (fullHD resolution of installer, AHCI mode on disks, boot drive partitioned as GPT and all...) but with R9 280X installed (flashed ROM or not) I only get that blue screen I attached in the first post.

You think that something else could be the cause?

Edit: The main thing I'm trying to figure out is if the problem is in homemade EFI ROM or card itself. The same way they didn't sort that millisecond glitches I have in 2D usage of the card.

 

[owbp]

So last night I tried one more time with MSI UEFI rom (it was overwritten) and everything I could get is this

That is a definitive no go then

Since I've managed to install with GT120 and Squuiid and ActionableMango are doing the same with EFI nVidias, does anyone know if it will work with PC Kepler/Maxwell cards or does it needs to be flashed?

 

[thornslack]

I ran into this issue with my flashed 780 and an unflashed TX putting win 10 on a samsung ssd. I had all sorts of install issues/corruption/reinstall/no bootable device problems. IIRC I pulled all my drives and had only my flashed gpu, installed the ssd on the backplane, installed win 10 efi from usb thumb, then installed nvidia drivers then bootcamp drivers. I shut it down, installed the pcie card, booted, allowed windows to install drivers, then shut it down and put the ssd on the card reinstalled and swapped the non flashed gpu back in. Everything works, except i have a ghost monitor left over from the original 780 being installed and I cannot switch between osx and win 10 short of pulling my win drive or resetting pram. I believe the issue and your issue are related to this thread but I never went back to verify or resolve in my case. You may also want to check the Win 10 experiences on cMP thread, I think the tail end also has some similar issues: Windows 10 Experiences on cMP

 

[owbp]

@thornslack ,
Thank you so much for sharing your experience and those links with me. It gave me strength for one more try
It seems that everyone's experience was different when installing Win10 EFI, except for guys who did it with no problems.

I have no trouble installing it with original nVidia GT120, but I had no where to go with flashed R9 280X, EFI rom or original UEFI rom - really didn't matter.
So after reading second linked topic I wanted to try it one more time. This time with deleting and then removing GT120 after installation and leaving just AMD drivers.
So installed Win10 with just one HDD, nVidia GT120 and AMD R9 280X, but monitor had to be connected to GT120 and then it works (no matter in what position is bios switch on AMD card).
After install, download AMD driver, install it, remove GT120 in Device Manager and reboot (in process you have to cancel the win reboot for several times).

The main problem, next to 2TB Hitachi HDD that I installed Win on and that sounds like tractor , is that I can boot into it just with GPU set to MSI's UEFI Hybrid BIOS, so no boot screens for me.
If I try to boot its with EFI Mac bios I get this message



So, I'm left with blind booting, using BootCamp Control Panel in Win 10 and using terminal bless command in OS X.