My work laptop is a Late 2013 MacBook Pro. Its current Apple BIOS version is 432.40.8.0.1 and its CPU is an Intel i7-4750HQ. It runs Ubuntu 22.04.4 LTS only. No dual boot, no VM.
My overarching goal is to apply an undervolt, as this laptop gets uncomfortably warm even under light loads and I'd also like to save power to reduce my environmental impact. I have already used georgewhewell/undervolt to undervolt my personal laptop and I attempted to do the same for this machine. However, I encountered the errors below which others were able to resolve by reverting to an older version of their BIOS. My BIOS is relatively new, so I'm assuming this is my issue as well.
Results of sudo python3 ~/.local/lib/python3.10/site-packages/undervolt.py -v --core -1 --cache -1:
INFO:root:Setting core offset to -1mV
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/0/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/1/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/2/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/3/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/4/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/5/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/6/msr
INFO:root:Writing 0x80000011ffe00000 to /dev/cpu/7/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/0/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/1/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/2/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/3/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/4/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/5/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/6/msr
INFO:root:Writing 0x8000001000000000 to /dev/cpu/7/msr
INFO:root:Read 0x0 from /dev/cpu/0/msr
ERROR:root:Failed to apply core: set -0.9765625, read 0.0
It looks like I might be able to roll back the firmware by reinstalling MacOS and following this procedure, but I'm worried about the time it would take to reinstall everything on this machine afterwards. I can't afford for it to be out of order for very long. I considered trying to make a bootable drive running MacOS following the procedure that way, but I'm still worried it either wouldn't work or I'd end up having to wipe the machine. Perhaps there's a way of completely backing up my install such that it would be relatively quick and easy to restore absolutely everything after reinstalling MacOS?
If there are other methods for undervolting Intel CPUs on Linux or other forums that this question would be better suited for, I'm all ears!
