Improving heat management after macbookpro 2011 discrete GPU fix, also a script to automate part of the fix process
Taken from StackExchange
Thanks to LangLangC
sudo mkdir -p /Library/LoginHook
sudo nano /Library/LoginHook/LoadX3000.sh
#!/bin/bash
kextload /System/Library/Extensions-off/AMDRadeonX3000.kext
pmset -a force gpuswitch 0 # undocumented/experimental
exit 0
Use
ctrl + o
to save andctrl + x
exit
sudo chmod a+x /Library/LoginHook/LoadX3000.sh
sudo defaults write com.apple.loginwindow LoginHook /Library/LoginHook/LoadX3000.sh
kextstat | grep AMD
... com.apple.kext.AMDLegacySupport (1.5.1) ...
... com.apple.kext.AMD6000Controller (1.5.1) ...
... com.apple.kext.AMDSupport (1.5.1) ...
... com.apple.kext.AMDLegacyFramebuffer (1.5.1) ...
And this
... com.apple.AMDRadeonX3000 (1.5.1) ...
should also appear on the list
Command + r + s
nvram boot-args="-v agc=0"
reboot
sudo nano /force-iGPU-boot.sh
#/bin/sh
sudo nvram boot-args="-v"
sudo nvram fa4ce28d-b62f-4c99-9cc3-6815686e30f9:gpu-power-prefs=%01%00%00%00
exit 0
sudo chmod a+x /force-iGPU-boot.sh
sh /force-iGPU-boot.sh
So I did this with my aging MBP, 15" Late 2011 high-mileage machine. I found I had to remove the AMDRaedonX3000.kext extension from /System/Library/Extensions even though I followed all the other steps creating the scripts, making changes to nvram etc. Now it works GREAT. Runs reasonably cool, the brightness keys work Perfectly and Sleep mode works Perfectly too. HOWEVER the only thing I have noticed is on boot, I get the dreaded gray (white?) screen for about 35 seconds before the Apple logo and progress bar appear. It makes me think it won't boot! After that its happy. Is this normal for this configuration after these changes? I get no clues looking through dmesg or /var/log/messages. Booting in verbose mode is not helpful either. Should I take out one of the scripts? Is it looking for the foo extension? Or should I make some other change? Or do nothing?
Thanks.