A macOS kernel extension (kext) for disabling CPU turbo boost to keep temperature (and fan noise) down.
Since System Integrity Protection (SIP) blocks unsigned kernel extensions, there are a few steps involved in enabling this kext:
- Reboot Mac into recovery mode by holding down cmd+R when booting
- While in recovery mode, open terminal and execute
csrutil enable --without kext - Reboot back into normal mode
- Open a terminal in the folder containing the kext and execute:
sudo chown -R root:wheel DisableTurboBoost.kext
sudo chmod -R 0755 DisableTurboBoost.kext
sudo kextload DisableTurboBoost.kext
Run kextstat |grep DisableTurboBoost to verify that it's loaded.
Run sudo kextunload -b no.vtek.DisableTurboBoost to unload the kext.
This small kernel extension will enable bit 38 of the MSR register MSR_IA32_MISC_ENABLE which causes the CPU to disable turbo boost.
There are some alternatives that enables bit 32 of MSR_IA32_PERF_CTL, but that didn't seem to have any impact on my system.
Take a look in the manual for more info.
I take no responsibility for whatever harm this kernel extension may cause your system. I use it myself without any issues, but I cannot guarantee it will work for you.
If you get this message when executing sudo kextload DisableTurboBoost.kext:
failed to load - (libkern/kext) not found; check the system/kernel logs for errors or try kextutil(8)
Try this command in stead: sudo kextutil -l DisableTurboBoost.kext
It will output something about invalid signatures, but the extension might still be loaded. Verify with kextstat |grep DisableTurboBoost.
The code was based on an outdated repo nanoant/DisableTurboBoost.kext.