MacOS not using discrete GPU no matter why I do...

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MacOS not using discrete GPU no matter why I do...

I have a 16' MacBook Pro with an AMD Radeon Pro 5500M. I am a Game Developer and using Unity to develop games. As I said in the title, my Mac is not using the discrete GPU which is resulting a very low fps in Play Mode in Unity. I also tried playing games (Sonic Racing) on my Mac and it still uses integrated GPU.

I switched off Automatic Graphics Switching for both Battery and Power Adapter.
I tried using gSwitch to force my Mac to use discrete GPU.
I tried using command line tools to force my Mac to use discrete GPU.
I forced Unity to use discrete GPU through Unity Preferences.
I tried using several Unity Editor versions (2019.4.28f1 (LTS), 2020.3.6f1(LTS), 2021.3.12f1(LTS))

None of these helped me. If you have any questions please feel free to ask.

Posted on Jun 29, 2021 2:46 PM

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Answer 1

Jun 29, 2021 5:00 PM in response to AhmetAy

Same results in Safe Mode? if problem is solved in Safe mode, "it's something you added."

Same results with an external display or TV set? there is no path to external displays from the Integrated graphics, so when these are in use ALL are moved to Discrete graphics..

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Answer 2

AhmetAy Author

Level 1

9 points

Jul 5, 2021 5:35 PM in response to Grant Bennet-Alder

Hi, sorry for very late response and my English in advance.

Unfortunately I couldn't test it in safe mode due to unbelievably low performance of my Mac in general in safe mode. It wasn't related to Unity, I couldn't lunch any application regardless. My mac was on 3 to 5 refresh rate at most (I don't know why).

But I figured something that I think I should share with you. On Unity version 2019.x.x, I can manually disable Metal framework on Unity Editor and switch to OpenGL Core. With this change, Unity started to use my discrete GPU and I was able to get 5k fps in an empty project instead of 50 to 60 fps with my integrated GPU.

I am able to switch Metal with OpenGL Core on Unity versions 2020 and 2021 but It had no effect on Unity to use my discrete GPU.

I don't have a monitor to test it out like you said but I was able to test it on my TV through AirPlay and It was using the discrete GPU like you mentioned. But the performance was no where near I get with OpenGL on Unity 2019.x.x, It was running about 200 fps in Playmode.

PS: My company forcing me to use Unity version 2020.x.x so I need a solution for that version of Unity.

I really appreciate the effort of you trying to help me, thank you in advance.

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Answer 3

Jul 5, 2021 6:31 PM in response to AhmetAy

If you can not get normal results in Safe Mode, "It's something you added." It seems clear that Unity is not cooperating with your discrete graphics.

Big Sur requires Big-Sur-ready Drivers, and older kernel extensions do not load properly. (That may be the problem.)

If you switched off Metal, and are using an older Unity, it may not load the correct graphics Drivers in safe mode. Also, the 5500 in your MacBook Pro was not released with OpenGL, it came AFTER Metal. so it is possible you do not have any support except Metal, and if you switch metal off, nothing works.

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Answer 4

AhmetAy Author

Level 1

9 points

Jul 7, 2021 4:02 PM in response to Grant Bennet-Alder

I re-installed my MacOS and without downloading anything else, I downloaded Unity version 2020.3.6f1 and the problem continues. Later I tested some other applications and all of them benefits my discrete GPU (I tested Blender and Shutter Encoder). I also tested latest stable and beta versions of Unity and nothing changes. I think this issue is related to Unity and Big Sur but not sure.

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Answer 5

AhmetAy Author

Level 1

9 points

Jul 13, 2021 4:01 PM in response to AhmetAy

I side installed macOS Catalina (as a secondary macOS, yes you can) to make sure this problem is not related to macOS version but turns out IT IS related to macOS version because in macOS Catalina, I was able to use my discrete GPU while using ANY version of Unity without a single problem. I hope Unity Team and Apple find a solution for people like me.

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Answer 6

hyou00

Level 1

18 points

Aug 15, 2021 12:10 AM in response to AhmetAy

Same problem here. Were you able to find any way to make it work?

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