MP 1,1-5,1 Opencore Legacy Patcher - preventing graphic acceleration

[Theoldgranary]

Hello,

I have an early 2009 Mac Pro 5,1 with 2 x 3.46 GHz 6-Core Intel Xeon, Sapphire Radeon RX580, 8gb GPU, MacOS Mojave version 10.14.6.

I have tried upgrading Mojave to Monterey using OpenCore Legacy Patcher version 0.6.4.

I had to remove the Sapphire Radeon RX580 and install the legacy Mac graphics card (NVidia GeForce GT120) 512 MB in order to see the ‘Boot screen’.

OpenCore Legacy Patcher installed the drivers for the ‘legacy Mac graphics card’ during the upgrade/installation of Monterey.

I can boot up and login to Monterey using the ‘legacy Mac graphics card’ however, when I shutdown the machine and install Sapphire Radeon RX580 card, It starts as normal showing the loading screen with apple logo and about 30% during the progress bar, the fans on the RX580 card stop and the screen goes black.

If I shut down and install the ‘legacy Mac graphics card’ it then boots in to Monterey without any issues.

I presume the issue is that ‘OpenCore Legacy Patcher’ has not installed the drives for the RX580 card and therefore is preventing graphic acceleration.

In ‘OpenCore Legacy Patcher’ I click on ‘Revert Root Patches’, shutdown, install the RX580 card and booted, however, the screen still goes black.

I have also tried to adjust the ‘SMBIOS Spoof Level’ to ‘Minimal’ shutdown, install the RX580 card and boot, however, the screen still goes black. When I revert to the ‘legacy Mac graphics card’ the ‘SMBIOS Spoof Level’ is back to Normal.

I have also tried the reinstall / upgrade to Monterey several times.

I think the ‘Revert Root Patches’ seems the logical thing to solve the problem, however, I am worried I am not doing something correctly.

Does anyone have any experience with this problem and if so are you able to describe the process in a little more detail as to how you ‘Revert Root Patches’ and at what stage you swop the ‘legacy Mac graphics card’ and install the RX580 card?

 

[Macschrauber]

You can turn on screen sharing, boot with the rx580 and remotely do OCLP assemble the bootloader with the RX580 in.

 

[Theoldgranary]

You can turn on screen sharing, boot with the rx580 and remotely do OCLP assemble the bootloader with the RX580 in.

Thanks. I have tried this remotely, however, with Rx580 installed, there is no boot screen to load the OCLP?

 

[Macschrauber]

If you have set up all properly the RX580 should display the OpenCore Boot Picker.

If it loads with the GT120 it should load with the RX580, too

If the OpenCore boot picker does not come up you have initial problems with your GPU like no valid GOP.

If the OpenCore boot picker comes up and loads Monterey you should get into the box remotely to control things.

 

[Theoldgranary]

I found a solution! Your comments about 'no valid GOP' got me thinking and in the end, I installed 'RefindPlus Boot Manager' which allowed me to boot into the OpenCore Patcher USB with the RX580 card and then install Monterey. All works fine. Thanks again for your support!

 

[Zs0lesz]

I found a solution! Your comments about 'no valid GOP' got me thinking and in the end, I installed 'RefindPlus Boot Manager' which allowed me to boot into the OpenCore Patcher USB with the RX580 card and then install Monterey. All works fine. Thanks again for your support!

Hello.
Could you please describe how you did it because I have a similar problem with Sapphire Nitro+ RX580 8Gb.
Thanks

 

[professor_mac]

Thanks guys. Saved me when I got caught with the same issue.