MBP 1,1-10,2 Dead GPU on MacBook Pro 8,2 (Early 2011), need to install Sierra to get sleep/brightness controls, but can't get installer to part 2

[izzy0242mr]

Classic case of a failed GPU on my MacBook Pro 8,2 (Early 2011 15"). I had High Sierra working and had done the GPU disabling commands, and everything was working except for sleep and brightness controls. Saw some people saying those worked (with the GPU disabled) on regular Sierra, so I thought I'd downgrade to that. Problem is I can't get the system to get to the second stage of the install process. No errors, just hangs. I figure it's because the GPU isn't disabled at that point, but I can't boot into single user or verbose mode because…there's no system installed. (I can boot into that off the Recovery drive but that doesn't let me run the GPU-disabling fixes outlined here).

Any ideas? I do have a separate M1 Mac and a newer Retina Intel Mac, as well as external connectors for the internal hard drives. Could I theoretically install Sierra onto the drive with another computer, then boot from it (and run the GPU-disabling commands before boot)? I feel like that'll run into the error of "you can't install Sierra on this computer" (because my other Intel Mac has a newer version of macOS on it).

 

[izzy0242mr]

SOLVED:

I installed Sierra from the USB installer like normal. However, before commencing the installation, I ran the NVRAM command in Terminal (not sure if this did anything).

Then, I let the installer proceed. It rebooted a few times and eventually got to the new user creation screen. I set that up but then it froze and crashed. THEN, I rebooted into single user recovery mode and followed the linked guide, disabled the failing GPU via commands, and it's all working great now. Sleep and brightness controls work, too. Seems like macOS Sierra is the one to stick with for the MBP8,2

 

[DCBassman]

Another experiment to try if it has any interest: make up a @dosdude1 patched Catalina USB installer. Upfront, do the single-user command line stuff to disable the Radeon. Then just install. Works flawlessly on both my 2011s, one early, one late.

 

[izzy0242mr]

Another experiment to try if it has any interest: make up a @dosdude1 patched Catalina USB installer. Upfront, do the single-user command line stuff to disable the Radeon. Then just install. Works flawlessly on both my 2011s, one early, one late.

Thanks. I think I tried Catalina and was still having issues with sleep and brightness, so not really sure what went wrong there. Might be worth a second shot though.