Looking for Apple EFI ROM for GTX 765m

[Lxixboss]

1- I have successfully installed an Nvidia Geforce GTX 765m from a Sager laptop into my 2011 Imac 27. Everything works fine except I get no boot screen or brightness control (I haven't checked if the Lightning port supports an external monitor).

2- I have also had a lot of success flashing PC video cards to work with Mac Pros (ATI HD 5770, ATI HD 7950, Nvidia GTX 680 mainly) thanks to the geniuses on this site and at Netkas.org. So I am conversant with the general procedure of backing up the existing BIOS in Windows or DOS (using atiflash or nvflash), then using Terminal to patch the BIOS in OSX and then going back to Windows or DOS to reflash the card with the patched BIOS.

3- I know that Apple used both the Nvidia Geforce GTX 755m and the Nvidia Geforce GTX 775m in their Late 2013 Imac 27's.

So... Has anyone or can anyone "frankenstein" an EFI BIOS from one or both of the two Apple cards to work on the aforementioned card? This would definitely help me out and, from what I have read, help out at least a few other people. It would also help right the injustice that Apple has inflicted on the user community (especially with the 2011 Imac 27's and their melting ATI video cards).

 

[mhren]

....So... Has anyone or can anyone "frankenstein" an EFI BIOS from one or both of the two Apple cards to work on the aforementioned card? This would definitely help me out and, from what I have read, help out at least a few other people. It would also help right the injustice that Apple has inflicted on the user community (especially with the 2011 Imac 27's and their melting ATI video cards).

Did anyone ever reply or did you find a ROM image?

As an aside ... is your GTX 765m working well with High Sierra too ?

 

[xmk]

Did anyone ever reply or did you find a ROM image?

As an aside ... is your GTX 765m working well with High Sierra too ?

Hello, Yes is working under High Sierra too!

 

[gsrandom]

Hello, Yes is working under High Sierra too!

Unfortunately, this won't be possible. The newer iMacs have the video on board, otherwise you would just be able to purchase the card directly and solve all your problems. So with that being said, there isn't a way to get "a" bios. This technique only worked due to the cards being removable and read in a pc or flasher.

You know you can fix your ATI incompatibility issues by installing a fresh copy of Mojave, booting that install disk on another Mac, go to the extensions folder and remove the amd3000 kext, then rebooting off the new install. No graphics issues or slow performance etc. Resorts to default amd drivers which are fine.

 

[arkieboy72472]

There is a whole 62 page thread in this forum with people who would love it if you find an answer. I would start reading it and maybe you will find some information. Maybe there is a way to do this and maybe not. Some guy in the Netkas forums and the macvideocards guy was both working on it but probably abandoned it. Brightness control has been solved but requires tools and knowledge few people possess. I have read on another forum where people are trying to mod files and add kexts to make it work. The person who can do this and extend the life of the A1312 will pretty much be a hero.