#amdgpu-fancontrol

A simple bash script to control the fan speed of AMD graphics cards

This is a simple bash script to control the fan speed of AMD graphics cards. The project has originally been forked from grmat/amdgpu-fancontrol and adjusted for my needs as a temporary tool to use while I work on my own, more elaborate solution. As such, I didn't invest much time to bring this up to my personal standards in regards to documentation, installation and ease of use.

The script can be configured via /etc/amdgpu-fancontrol.cfg (example configuration). A systemd service configuration as well as a PKGBUILD for Arch-based distributions are available.

#My changes

Note: Due to a bug, the current PWM value is not reported accurately (it always shows 0) with the fan mode set to manual (so when using this script), at least on some cards (including my RX 6900 XT). This doesn't mean this script doesn't work correctly: adjusting the PWM value still works fine, it's just the hwmon readback that's wrong (which has no influence on the functionality of the script, aside from resulting in incorrect debug output). This issue will supposedly be fixed in kernel 5.12. See here for details (particularly this comment).

• By default, temp2_input is used, which should be the junction temperature on RX 5xxx series cards and newer. This temperature represents the hottest point at any given moment and is also what is used to control custom fan curves in Windows
• By default, a more aggressive fan curve is used (40% at 60 °C, 50% at 65 °C, 75% at 80 °C, 100% at 95 °C). I have removed fan stop altogether as it doesn't seem to work when the fan mode is set to manual (at least on my RX 6900 XT). I usually just run with automatic fan mode only use the custom fan curve when I stress the card (e.g., when gaming). That way, I can still use fan stop during regular desktop usage
• Changed the hysteresis value (the temperature drop required before the script lowers the fan speed) from 6 °C to 4 °C
• The systemd unit will attempt to restart up to 6 times if it fails (e.g., if the hwmon paths are not yet available during boot), pausing 5 seconds after each attempt
• Added a failsafe in case the temperature readout suddenly becomes unavailable: it first sets (or attempts to set) the fan speed to 100%, waits 3 seconds and finally sets the fan mode back to automatic and exits
• Further quieted down the output when not using debug mode to prevent journal spam