Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

DJ Dilbert

macrumors regular
Original poster
Apr 2, 2010
188
108
Pittsburgh, PA
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!
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
Install the AppleOEM GPU, use the boot picker to boot from a createinstallmedia USB High Sierra installer, fully erase your main drive, reinstall. After everything is updated, install the current NVIDIA web drivers and finally change the GPU.
 

DJ Dilbert

macrumors regular
Original poster
Apr 2, 2010
188
108
Pittsburgh, PA
Install the AppleOEM GPU, use the boot picker to boot from a createinstallmedia USB High Sierra installer, fully erase your main drive, reinstall. After everything is updated, install the current NVIDIA web drivers and finally change the GPU.

I tried that. I let the installer run but it just hangs on the initial progress bar. I thought maybe it was just slow as it's over a USB 2.0 connection, but I let it run overnight and I woke up to it still just hanging at the full progress bar. I'm not sure what is wrong.
 

tsialex

Contributor
Jun 13, 2016
13,459
13,608
I tried that. I let the installer run but it just hangs on the initial progress bar. I thought maybe it was just slow as it's over a USB 2.0 connection, but I let it run overnight and I woke up to it still just hanging at the full progress bar. I'm not sure what is wrong.
Enable verbose boot and see where is stopping for any clues?
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.