MacBook Pro 15" 2011 GPU question

[Muhammad Reza]

Hello guys,

I had recently disabled my AMD dGPU on my MacBook Pro 15" from 2011 since it was starting to show it's age (usually it worked fine for the last 7+ years but sometimes it would start to show symptoms of nearing failure which was common on the 2011 models so I stepped in and finally decided to disable the GPU before it bricks itself, disabling me the access to the terminal since switchable GPU MBPs always boot from dGPU first).
This is the guide I used for disabling the AMD dGPU: https://gist.github.com/cdleon/d1eff7246a25193304284ecec40445b0

Since the GPU was disabled and saw MacOS Catalina was released I wanted to finally get off High Sierra in favor of an OS that actually integrates darkmode, so I followed dosdude's guide on the MacOS Catalina patcher which went seamlessly and now MacOS Catalina is in fully working state in my MBP, small anomalies such as light mode having weird dark-gray colors and no transparency but nothing to worry about (Dark mode is just fine).

After I installed Macs Fan Control (I like my mac running cool rather than quiet) I saw that the GPU is running in the high 40s/low 50 degrees Celsius range and I was wondering if my dGPU was working inside Catalina so I went into terminal and used the following command to see if my GPU kext was picked up.

kextstat | grep AMD
... com.apple.kext.AMDLegacySupport (1.6.8) ...
... com.apple.kext.AMD6000Controller (1.6.8) ...
... com.apple.kext.AMDSupport (1.6.8) ...
... com.apple.kext.AMDLegacyFramebuffer (1.6.8) ...

But the kext for actually running the dGPU com.apple.AMDRadeonX3000  was not present in the OS (it was in High Sierra), which made me sure that the GPU was at idle if on at all. I even installed gfxCardStatus to see the current used graphics device which had shown the Intel iGPU. So I am wondering if the GPU is still on and heating up for no reason or if it's just measuring the temperature of the GPU which gets hotter because the CPU runs on the same heatsink?

My MBP specs:

15" MacBook Pro, late 2011
2.2GHz Intel Quad-Core i7 (2675QM)
16GB DDR3 RAM
AMD Radeon HD 6750M  512MB (disabled)
240GB SSD
Upgraded anti-glare screen with higher than stock resolution.

I have no issues with the MBP regarding stability or too much heat output but if the GPU is actually on and drawing power/heating up then I would like to know a way to bypass that which would enhance my thermals and presumably battery life as well.

[caincha]

Are you able to boot into MacOS?

If so download and run this dosdude's dGPU disabler: http://dosdude1.com/apps/MacBook Pro dGPU Disabler.zip

You might need to disable SIP before installing this app:

-Open Recovery Mode on startup (command+R), open Terminal and run:

csrutil disable

 

If you can't boot into MacOS or Recovery Mode then 

-Insert USB with bootable OSX in it

-Press Option key at boot, position the mouse on the MacOS installer icon.

-Click the MacOS installer icon whilst holding the Command + S keys until boot into Single User

-After all is loaded in a DOS-like screen run:

nvram fa4ce28d-b62f-4c99-9cc3-6815686e30f9:gpu-power-prefs=%01%00%00%00

reboot

 

Then go back and disable SIP boot into the system and install/run that dusdude's app. 

After that never ever reset PRAV/SMC or your laptop will crash and you'll have to go through all this again…

[Muhammad Reza]

Yes, I am able to boot and work normally on Mac OS Catalina.

The same nvram line was present in the guide I linked above in my first post, and as far as I know the GPU is disabled but I will try that dGPU disabler zip. I am just wondering why the temperature of the thing seems high for something thats idle/disabled, unless its a shared temperature with the CPU since both share the same heatsink.