Step 1

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

Locate OpenCore-Patcher icon in Applications folder and double-click on it to run it.

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 will be working very slow. It's because your system is now running without any patches.

Wait a few seconds and you 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 the 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.

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

Step 8

Click Download macOS Installer button.

Step 9

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

Step 10

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

Step 11

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

Step 12

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

Step 13

Select the just downloaded macOS installer version from the list.

Step 14

Select your USB flash drive from the list.

Step 15

Click Yes button to confirm erasing the USB flash drive.

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

Step 16

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

Step 17

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

Step 18

Choose your USB flash drive from the list.

Step 19

Click the only EFI volume on your USB flash drive.

Step 20

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

Step 21

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 22

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

Step 23

Choose Install macOS... from the list.

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

Step 24

Click Continue button.

Step 25

Click Agree button to accept licence agreement.

Step 26

Again click Agree button.

Step 27

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 28

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 29

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 30

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.