Here comes another dedicated GPU (dGPU) issue on my Late 2013 15" MacBook Pro!
Problem:
My NVIDIA GeForce GT 750M idles hotter than other MacBook Pros with the same dGPU, using up 17W of power at idle. This heats up my CPU +10c when dGPU is enabled and just idling, due to the fact that they share a heat pipe. This is also problematic by contributing unnecessary heat when connecting an external 4k monitor. Many people have reported issue with overheating trying to run a second high resolution monitor.
Background:
It's running the latest MacOS Catalina. I repasted CPU/GPU with Grizzly Kryonaut and the CPU runs really cool now.
While stress testing the CPU, I noticed that the CPU will run 10c hotter when the dGPU is enabled.
I checked the idle temperatures and the dedicated GPU temp increases from 37c when disabled to 60c when enabled. I checked with 2 different MacBook Pros with the same dedicated GPU and they idle around 48c.
I checked the dGPU load with Activity Monitor and it's fine, almost no load.
I have a feeling the dGPU is not using its low power states. I have not found any app or utility that will show me the GPU frequency in MacOS. However, I did find that "HWMonitor" can read the "GPU Rail" power consumption. The GPU rail consumption is 0.11W with the iGPU enabled. Enabling the dGPU brings the power consumption to 16W at idle! Booting into safe mode, the dGPU is used by default and draws 3W. I was even able to boot normally with automatic graphics switching disabled (uses dGPU) and it draws the normal 3W. However, if I toggle automatic graphics switching on and back off (switches to iGPU and back to dGPU), then it becomes stuck at 16-17W again until rebooting with dGPU on.
Does the MacBookPro 11,3 on Catalina still use AppleGraphicsPowerManagement.kext to manage the power states? If not, where is it done? I noticed AppleGraphicsPowerManagement.kext doesn't even load on its own, but it does on my sister's MBP with the 750M running Mojave.
Does anyone have any suggestions about how to diagnose this further or fix it?
Problem:
My NVIDIA GeForce GT 750M idles hotter than other MacBook Pros with the same dGPU, using up 17W of power at idle. This heats up my CPU +10c when dGPU is enabled and just idling, due to the fact that they share a heat pipe. This is also problematic by contributing unnecessary heat when connecting an external 4k monitor. Many people have reported issue with overheating trying to run a second high resolution monitor.
Background:
It's running the latest MacOS Catalina. I repasted CPU/GPU with Grizzly Kryonaut and the CPU runs really cool now.
While stress testing the CPU, I noticed that the CPU will run 10c hotter when the dGPU is enabled.
I checked the idle temperatures and the dedicated GPU temp increases from 37c when disabled to 60c when enabled. I checked with 2 different MacBook Pros with the same dedicated GPU and they idle around 48c.
I checked the dGPU load with Activity Monitor and it's fine, almost no load.
I have a feeling the dGPU is not using its low power states. I have not found any app or utility that will show me the GPU frequency in MacOS. However, I did find that "HWMonitor" can read the "GPU Rail" power consumption. The GPU rail consumption is 0.11W with the iGPU enabled. Enabling the dGPU brings the power consumption to 16W at idle! Booting into safe mode, the dGPU is used by default and draws 3W. I was even able to boot normally with automatic graphics switching disabled (uses dGPU) and it draws the normal 3W. However, if I toggle automatic graphics switching on and back off (switches to iGPU and back to dGPU), then it becomes stuck at 16-17W again until rebooting with dGPU on.
Does the MacBookPro 11,3 on Catalina still use AppleGraphicsPowerManagement.kext to manage the power states? If not, where is it done? I noticed AppleGraphicsPowerManagement.kext doesn't even load on its own, but it does on my sister's MBP with the 750M running Mojave.
Does anyone have any suggestions about how to diagnose this further or fix it?
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