Swapped a Radeon VII for 6900XT Red Devil (xtx) but won't work (Big Sur)

[jadfer]

I have a working Hackintosh, running Big Sur 11.6.1 with a Radeon VII, and so far it works fine for my needs. I used opencore .78 and the Dortania setup guide.

I wanted to speed up video transcodes by installing the powercolor 6900XT red devil, so I took out the VII and popped this one in. I booted it up and it got to about 20% on the apple logo screen and the screen went black. I then added the agdpmod=pikera and it had no effect. I checked the AAPL,ig-platform-id and its set to 0300913E.

I even went as far as attempt to install a fresh copy on a new drive, with the original installer (with pikera boot arg) and it had the same effect, black screen.

I tried all 4 ports (1xhdmi, 3xDP) with the same results.

I verified the card in Windows and its device id is _73BF, subsys _2408148C and according to techpowerup and other sources is an XTX card.

As most users I have seen posting about this card say that it works out of the box, I have had a hard time finding ways to troubleshoot the issue. Most solutions are based on XTXH and spoofing, which I should not need to do.

I would appreciate assistance pointing me in the right direction to troubleshoot this issue.

 

[zirkaiva]

Try this solution:

AMD Radeon RX 6800 XT / 6900 XT for macOS?

I have created a patch that allows AMD RX6600/RX6800/RX6900 cards to work on a Mac Pro 4,1/5,1 (and maybe a 3,1? I have no idea if that's even possible). I examined ROM dumps of RX6600/6600XT and RX6800/6800XT/6900XT from various manufacturers, and every one I looked at used the same (broken)...

forums.macrumors.com

 

[jadfer]

I am using smbios 19,1 to match the hardware, the thread talked about the old mac pro cheesegraters, not sure if it would work on my system.

 

[TronEffect]

I am using smbios 19,1 to match the hardware, the thread talked about the old mac pro cheesegraters, not sure if it would work on my system.

Hey bud, you ever figured it out?
I think i am having similar issue. Except i am coming from a Sapphire Vega 64 to a Sapphire 6900XT Nitro+ SE.

Popped this card in and got black screen... thought it was my Opencore version... and decided to try to re-install and even that i am still having issues.
been trying to use the latest 0.8.5 and 0.8.4 opencore... MacOS Montery