Black Screen after NVRAM reset

manuel.schmid wrote:

Unfortunately I did not get an answer from OCLP community. I tried a different GPU that worked. I assume, OCLP makes a setting to NVRAM that enables older GPUs to support metal. As I could not restore this NVRAM setting, I had to exchange the old GPU to a newer supporting with native metal support.

I wouldn’t assume anything with OLCP. Best case it does what it claims, and if it works, it works. If not, maybe you can revert.

And as mentioned above, have a bootable macOS 10.14 with Metal or have bootable macOS 10.13 without, preferably on a bootable USB device, and also preferably have complete and current backups.

I’m migrating data off of a cheese-grater I’m now dealing with, as it is seriously excessive for what the user is now doing with it.

Sooner or later, this old Mac Pro cheese-grater is going to tip over, whether maybe OCLP or probably otherwise.

Contact the OCLP folks.

"Best Practice" when heading off the beaten trail into alternative boot loaders is to have an unmodified standard version of MacOS available to boot from when things go badly. The last version your Mac can boot from without ANY changes or additions is usually a good choice.

For the Mac Pro 5,1 withOUT Metal graphics card, that would be a standard MacOS 10.13 High Sierra drive. Then you CAN use Alt/Option-Boot to get back to reality, check things out and make sure everything is still working normally.

Once you have STANDARD MacOS working, you can get your alternative boot loaders and all its features loaded and going again, and move forward under those rules without additional difficulty of 'nothing seems to work'.

Hi, I'm got a so same issue as Yours, could You get any help for Your "little" problem?

mac mini late 2012 model 6,2