GUIDE How to Enable AMD RX 6800, RX 6800XT and RX 6900XT on macOS Big Sur and Later

[snooksy]

Provide system specs.

Is this sufficient?

 

[EliteMacx86]

View attachment 7338
Is this sufficient?

Yes, a copy of IOReg is also needed.

 

[snooksy]

Provide system specs.

Hi again,

I was away for a bit with the family over Easter. Zip file attached with IOReg dump.

 

[EliteMacx86]

Hi again,

I was away for a bit with the family over Easter. Zip file attached with IOReg dump.

No worries.

 

[mrdarkd]

I've encountered a problem. Everything works perfectly on RX 580, but when trying to install 6900XT, I get a black screen during loading (when trying to boot from a Sequoia installation flash drive using opcore efi). I built the EFI using opcore simplify. I've checked everything described in this article, and everything matches. In BIOS, I tried enabling/disabling rebar, 4G decoding, CSM/UEFI, disabled iGPU, WiFi/BT, and tried all available SMBIOS. I tried all video outputs, even connected a USB-C to HDMI adapter. None of the ports work. Does anyone have any ideas about what might be wrong?

 

[EliteMacx86]

I've encountered a problem. Everything works perfectly on RX 580, but when trying to install 6900XT, I get a black screen during loading (when trying to boot from a Sequoia installation flash drive using opcore efi). I built the EFI using opcore simplify. I've checked everything described in this article, and everything matches. In BIOS, I tried enabling/disabling rebar, 4G decoding, CSM/UEFI, disabled iGPU, WiFi/BT, and tried all available SMBIOS. I tried all video outputs, even connected a USB-C to HDMI adapter. None of the ports work. Does anyone have any ideas about what might be wrong?

Remove the device ID if your card is not an XTX variant. Also, -radcodec and then check.

 

[mrdarkd]

I've encountered a problem. Everything works perfectly on RX 580, but when trying to install 6900XT, I get a black screen during loading (when trying to boot from a Sequoia installation flash drive using opcore efi). I built the EFI using opcore simplify. I've checked everything described in this article, and everything matches. In BIOS, I tried enabling/disabling rebar, 4G decoding, CSM/UEFI, disabled iGPU, WiFi/BT, and tried all available SMBIOS. I tried all video outputs, even connected a USB-C to HDMI adapter. None of the ports work. Does anyone have any ideas about what might be wrong?

problem solved. I changed bios jumper on my 6900xt from OC to Silent and it helps.
my current bios settings:
csm: disabled
wifi/bt: disabled
pci mode: gen3 for all
rebar: disabled
igpu: disabled
above 4g decoding: disabled
svm: disabled
all boot devices to uefi mode