Resolving Black Screen Issue on Mac Pro 5.1 with ASUS AMD ROG Strix RX 560 after Booting Ventura

Guide Step by Step:

1. Understanding the Issue:

   • Upgrading to an ASUS AMD ROG Strix RX 560 in a Mac Pro 5.1 can cause display issues, especially when switching from an NVIDIA GT 120.
   • The black screen after selecting the Ventura boot drive suggests a problem with graphics card initialization.

2. Check EFI Configuration:

   • Ensure your EFI folder is correctly set up for the RX 560.
   • Verify that the latest versions of Lilu and WhateverGreen kexts are installed. These kexts are crucial for proper graphics card functionality.

3. Monitor Connection:

   • Even though you are using a new HDMI cable, try connecting via a different port on the graphics card if available (e.g., DisplayPort).
   • Some GPUs have specific port preferences when booting.

4. Boot in Verbose Mode:

   • Boot in verbose mode to see if there are any specific error messages. Add -v to your boot arguments in the EFI configuration.
   • This can provide clues as to where the boot process is failing.

5. Graphics Card Power Requirements:

   • Check that your Mac Pro’s power supply and PCIe power connectors can adequately support the RX 560.
   • Insufficient power can lead to boot issues.

6. macOS Version and Compatibility:

   • Verify that macOS Ventura is fully compatible with your Mac Pro 5.1 and the RX 560.
   • While the RX 560 supports Metal and should work with Ventura, other system incompatibilities might exist.

7. Reset NVRAM:

   • Resetting the NVRAM can sometimes resolve boot issues. Turn off your Mac, then turn it on and immediately press and hold the Option, Command, P, and R keys.

8. Test with Original GPU:

   • Reinstall the NVIDIA GT 120 and see if the system boots correctly. This can confirm whether the issue is isolated to the RX 560.

9. BIOS/UEFI Settings on GPU:

   • Some GPUs have a dual BIOS/UEFI mode. Ensure your RX 560 is set to a compatible mode with your Mac Pro.

10. Check for Physical Issues:

    • Inspect the RX 560 for any physical damage or improper seating in the PCIe slot.

11. Seek Community Help:

    • Post in Mac Pro and Hackintosh forums with your issue, including detailed descriptions of what you've tried. Community members might have faced similar issues.

12. Alternative Solutions:

    • If the problem persists, consider using a different macOS-compatible GPU or reverting to a macOS version more stable with your hardware.

Remember, hardware upgrades in older Mac Pros can be tricky due to compatibility and power constraints. Careful troubleshooting is key to identifying the cause of the issue.