Arch Linux

nathanwoodburn

Member

Registered: 2025-09-03

Posts: 1

AMD Ryzen 9 8945HS CPU stuck at low frequency on external power

G'day,
I’m running Arch Linux (kernel 6.16.4-arch1-1) on a Pangolin Pang15.
- AMD Ryzen 9 8945HS (16) @ 5.26 GHz
- AMD Radeon 780M Graphics
The CPU always stays at its lowest frequency, even when connected to an external monitor that provides power over USB-C.
cpupower shows:

driver: amd-pstate-epp
energy performance preference: performance
hardware limits: 403 MHz - 5.26 GHz
current policy: frequency should be within 1.10 GHz and 5.26 GHz.
                  The governor "performance" may decide which speed to use within this range.

The scaling_driver files confirm `amd-pstate-epp` is being used.

Things I’ve tried:
- Switching to acpi-cpufreq (same behavior)
- Installing/uninstalling TLP and system76-power
- Setting the governor to performance from balance_performance

Still, the CPU sticks to low frequencies.
Screenshots:
https://upload.woodburn.au/27d/2025-09- … prshot.png
https://upload.woodburn.au/Uv7/2025-09- … prshot.png
https://upload.woodburn.au/aAu/2025-09- … prshot.png

Any ideas how to get it to scale up the clock frequency properly?

Last edited by nathanwoodburn (2025-09-03 06:40:00)