Can someone help me troubleshoot my issue? I have installed a radeon Vega 56 GPU in my Mac Pro 2009 5,1 but I get no video. Have aux power to both 8 and 6 pin power slots. Running 10.13.6.
Computer boots, but black screen. Thoughts?
So here was my solution: My issue seemed to be a power issue. I performed/did/installed the Pixlas mod, grabbing power straight from the PSU and not from the motherboard. Computer booted right up and as expected the video came on after the drivers were loaded. No boot screen available, which is fine with me.