I have a 2010 5,1 Mac Pro. I recently upgraded my hardware to 2, 6-core x5690s, 64GB ram and a GTX 1060 6G. My next move was to upgrade the OS to Mojave, but I didn't know that Nvidia's web drivers were not supported in Mojave. So per Apple Support's instructions, I swapped out the Nvidia card for my original ATI 5870 and attempted a time machine restore to my SSD to downgrade back to High Sierra. Note that all my hardware was running perfectly when before I upgraded the OS.
TL;DR, I screwed something up and I'm not sure what. I now get a flashing folder when powering up (suspecting the OS got corrupted). I also cannot boot into recovery mode either, nor can i do internet recovery or select a disk to boot from (for my USB boot drive for High Sierra).
I'm fresh out of ideas. Please let me know if i need to provide any additional details. I can still create files on my Macbook Pro if need be.
Thank you in advance!
TL;DR, I screwed something up and I'm not sure what. I now get a flashing folder when powering up (suspecting the OS got corrupted). I also cannot boot into recovery mode either, nor can i do internet recovery or select a disk to boot from (for my USB boot drive for High Sierra).
I'm fresh out of ideas. Please let me know if i need to provide any additional details. I can still create files on my Macbook Pro if need be.
Thank you in advance!