Step 1

Remove your new graphics card and put you old graphics card inside Mac Pro.

Run OpenCore Legacy Patcher and enter your username password then click OK button.

Step 2

Click Post-Install Root Patch button.

Step 3

Click Revert Root Patches button to remove all patches for your current system and graphics card.

Step 4

Click Ignore button, close all opened applications and turn off your computer.

Step 5

Replace your old graphics card with a new one and start your computer again.

If your computer boots successfully you will be presented with white desktop wallpaper and everything would be working very slow. It's because your system is now running without any patches.

Wait a few seconds and your should see OpenCore Legacy Patcher popup window, telling you are running the system without Root patches and if you would like to install them. Click OK button to install all necessary patches.

Warning: If your system still boots to black screen please skip to Step 7.

Step 6

Click Reboot button to restart the system. Post restart your system would boot with a new graphics card and there will be no more black screen.

Step 7

If your system still boots to black screen you need to refresh macOS install by booting some older bootable system e.g. Mojave.

If you don't have any older bootable system you can use your old graphics card for a moment again just to recreate the USB stick.

Run OpenCore Legacy Patcher and enter your username password then click OK button.

Please note: All your data and settings will remain in place during macOS refresh install.

Step 8

Insert a USB flash drive which is at least 16 GB in size. Click Create macOS Installer button.

Step 9

Click Download macOS Installer button.

Step 10

Choose macOS version you wish to refresh. You can also upgrade older versions of macOS. Then click Download button.

Step 11

Ignore the warning and click Download Anyways button to start downloading macOS installer.

Step 12

macOS installer would be downloaded. It will take several minutes depending on your Internet connection speed.

Step 13

Click Yes button to create macOS installer on a USB flash drive.

Step 14

Select the just downloaded macOS installer version from the list.

Step 15

Select you USB flash drive from the list.

Step 16

Click Yes button to confirm erasing the USB flash drive.

WARNING: All data on your USB flash drive would be lost!

Step 17

It will take several minutes to copy macOS installer onto flash drive depending on the write speed of your USB flash drive.

Step 18

Now click Install to disk button to install OpenCore Legacy Patcher on your USB flash drive.

Step 19

Choose your USB flash drive from the list.

Step 20

Click the only EFI volume on your USB flash drive.

Step 21

Click Ignore button, close all applications and turn off your computer.

Step 22

WARNING: If you have used your old graphics card to boot the system now replace it with your new graphics card. Otherwise the system would be patched for the old graphics card again.

Start the system while pressing Option key (or ALT key) and click an arrow under EFI boot screen icon with OpenCore logo.

Step 23

On OpenCore Legacy Patcher boot picker click an arrow under Install macOS... icon to run the installer from a USB flash drive.

Step 24

Choose Install macOS... from the list.

WARNING: Make sure not to use Disk Utility here otherwise data on your hard drive would be lost!

Step 25

Click Continue button.

Step 26

Click Agree button to accept licence agreement.

Step 27

Again click Agree button.

Step 28

Choose the drive with already existing macOS installation and click Continue button.

Alternatively you can choose an older macOS drive here instead if you want to upgrade it and make it functional with your new graphics card.

Step 29

It will take about an hour to refresh or upgrade the system with all necessary patches. The system will restart several times, but this process is fully automated. Just wait for it to finish.

Step 30

Once the installation is done you might be asked some questions about Siri etc., but finally you will be presented with welcome screen.

Just click an arrow under the text to see the desktop. All your data and settings will be back and your new graphics card will now be fully functional. Enjoy!

Step 31

If you have already installed OpenCore on your hard drive you can ignore this popup message. If not you can click OK button to install it.