This repository offers an easy way to undervolt a Steam Deck as safely as possible and without entering the BIOS or disabling read-only using RyzenAdj and systemd targets based on Chris Down's guide.
A precompiled version of RyzenAdj is provided for your convenience, built in Arch Linux from commit f6fbf9d17f70d9736bc8294ccd8438ae94804aa9.
As with any undervolt exercise caution, while this project greatly reduces the risk of bricking your deck, it does not in any way guarantee you won't damage your hardware. Use at your own risk.
Inside this repository is a home and etc folder, use this as a template to add these files to the root of your Steam Deck (You will need root to add files to the etc folder, and they will survive SteamOS updates).
Once completed, run the following to apply the added udev config:
sudo udevadm control --reload-rules
The undervolt amount can be changed by editing /home/deck/.local/bin/set-ryzenadj-tweaks.sh
By default a -5 curve optimization is applied (via -set-coall), which should be stable on most hardware.
sudo systemctl start set-ryzenadj-tweaks.service
Once you're happy with the undervolt and confirmed it's stable, run the following to ensure the undervolt is reapplied automatically going forward:
sudo systemctl enable set-ryzenadj-tweaks.service