2011 MBP has the usual GPU failure and I had been running the computer while forcing the discrete card to not install by deleting the driver files. I then made the mistake of trying to install Yosemite completely forgetting that the drivers would get reinstalled. Now the install hangs on the Apple logo screen at 50%. I think it's hanging because it is trying to boot with the discrete graphics card.
I've tried resetting the PRAM/NVRAM, rebooting to Safe Mode, Diagnostics and everything else I can think of. The only thing I can do is boot into Single User Mode. I've run fsck -fy and everything checks fine. I can see the Yosemite install app but the drive is write protected so I can't make changes (see attached image)
Any ideas how I can cancel the install or get around the discrete card to finish the install?
I've tried resetting the PRAM/NVRAM, rebooting to Safe Mode, Diagnostics and everything else I can think of. The only thing I can do is boot into Single User Mode. I've run fsck -fy and everything checks fine. I can see the Yosemite install app but the drive is write protected so I can't make changes (see attached image)
Any ideas how I can cancel the install or get around the discrete card to finish the install?
