Set P-State voltages and clock speeds on recent AMD CPUs on Linux.
This software can damage your hardware, use at your own risk.
Tool for changing voltages and clock speeds for AMD processors with control over every power state and CPU core.
You can compile with the program make.
Make the binary executable chmod +x amdctl.
Run the program for a list of options, you can type ./amdctl to run it.
Undervolting is done by increasing the value of the CpuVid field for a specific P-state.
This can be done by invoking 'sudo /path/to/amdctl -pP -vV' in console, where P is the P-state of which the CpuVid you want to change and V is the value you want the CpuVid field to have.
For example, 'sudo /path/to/amdctl -p1 -v25' will change the value of the CpuVid field of P-state #1 to 25.
This applies the undervolt to all cores. You can specify a core by using the -c flag.
AMD CPU family's 10h(K10), 11h(Turion), 12h(Fusion), 15h(Bulldozer), 16h(Jaguar), 17h(Zen - Untested).
Note that Zen/17h has not been tested, I only modified the program based on the AMD programming reference, use with caution.
This would be most AMD CPU's between 2007 and 2018.
You can find your CPU family by typing cat /proc/cpuinfo in a terminal, the values there are in decimal.
10h is equivalent to 16, 16h 22 for example.
The program will check if your CPU is supported when run.
AMD CPU family 9h(K9) and earlier.
AMD 13h, I could not find any info on this, so I assume this CPU family does not exist.
AMD 14h(Bobcat) family, these have a different way of calculating clock speed, without a CPU to test I won't attempt to support them.
Anything newer than 17h (for now).
Root access.
Msr kernel module.
To manually load the msr module: sudo modprobe msr
To automatically load the msr module see the arch wiki.
https://developer.amd.com/resources/developer-guides-manuals/
https://wiki.archlinux.org/index.php/K10ctl
http:https://sourceforge.net/projects/k10ctl/
https://web.archive.org/web/20090914081440/http:https://www.ztex.de/misc/k10ctl.e.html
https://01.org/msr-tools
https://en.wikipedia.org/wiki/List_of_AMD_CPU_microarchitectures
http:https://users.atw.hu/instlatx64/