Taken from 2011 Macbook Pro Graphics Card FIX 100% WORKING!!!
EDIT This method works! But there is an improved version for better thermal management and brightness keys functionality. See improved version -> https://gist.github.com/cdleon/d1eff7246a25193304284ecec40445b0
if you are on high sierra 10.13.6+ you might need to use
Command + rinstead
Boot up holding down Command + r + sSIP locks System folder so cannot move kexts to another folder. SIP (csrutil) only enabled or disabled on Recovery Mode.
csrutil disablerebootboot up holding down the CMD and S keysuse /sbin/fsck if you get fsck command not found
fsck -fyuse /sbin/mount if you get mount command not found
mount -uw /sudo mkdir /AMD_Kexts/sudo mv /System/Library/Extensions/AMD*.* /AMD_Kexts/sudo rm -rf /System/Library/Caches/com.apple.kext.caches/sudo mkdir /System/Library/Caches/com.apple.kext.caches/sudo touch /System/Library/Extensions/Unmount a partition to guarantee that your changes are flushed to it. Use /sbin/umount if you get umount command not found. It might say resource busy, ignore that and proceed to next step)
sudo umount /sudo rebootBefore enabling SIP again, try the normal boot without pressing any key. The Mac OS will rebuild the kernel cache and restart. See if the system starts normally. If it does, still keep going through the remaining steps.
You might encounter that you are still using discrete GPU but computer works (if you are using gfx it might say can't change to discrete while external display is connected), keep going until last step and this will be resolved
if you are on high sierra 10.13.6+ you might need to use
Command + rinstead
Command + r + scsrutil enablerebootsudo nvram fa4ce28d-b62f-4c99-9cc3-6815686e30f9:gpu-power-prefs=%01%00%00%00sudo shutdown -r nowYou might need to do this again after macOS system updates Brightness keys might not work use app like brightness-slider to handle that
Unless you have tested this procedure on the specific hardware in question, and are willing to support any issues encountered by the user, you shouldn’t be suggesting it. Especially to someone who isn’t technically advanced, as is the case here. You yourself stated it didn’t run well when you did this. For basic users who aren’t highly technical, it’s irresponsible to suggest going beyond the OS version Apple officially supports, or recommending other technical modifications to the OS. I doubt the user here has any idea what “OpenCore Legacy Patcher” is, let alone what to do with it.
I could try doing this myself, but I also have almost 50 years of experience working with computer systems. I know what precautions to take, so that if anything goes wrong, I have the knowledge and tools to get my system working again.
(I won’t be making any further replies to subsequent comments regarding this. So, if your ego insists you “put me in my place”, feel free to do so. I couldn’t care less.)