Valve has put out SteamOS 3.9.6 as a beta, and its main job is to stop games from running slower than they should when you cap the frame rate. Take a title that renders 30 frames a second with the cap set to 60, shown on a 120 Hz panel: the old build could land it at 24. Valve says a capped game whose frame rate divides evenly into the limit no longer falls under it.
The beta reaches Steam Deck owners and other SteamOS users who opt in under Settings, System, System Update Channel, on the Beta or Preview channel. Valve’s notes cover everything changed since the current stable release, SteamOS 3.8, so someone moving over from stable gets the earlier 3.9 work as well as the new fixes.
The frame-timing changes come in three parts, according to Valve’s patch notes. Valve improved timing when the limiter runs with variable refresh rate, improved it again when the limiter runs without VRR, and cut the missed frames on fixed-refresh screens that were caused by slow wakeups from deep CPU idle states. Separately, it fixed games running below the refresh rate on 240 Hz and faster displays, which matters for anyone plugging a handheld or small PC into a high-refresh monitor.
Colour gets a fix too. On displays without a wide colour gamut, HDR10 output made SDR material look too saturated, and the notes list that as fixed.
The rest of the list is a set of smaller repairs:
- a black screen in RPG Maker games that use Fullscreen++, such as Waste Walkers;
- a green screen in Steam Remote Play on NVIDIA GPUs;
- left click sticking after a two-finger tap on the touchscreen;
- gamemode and other LD_PRELOAD libraries breaking when launched through gamescope;
- several rare crashes and memory errors on shutdown and when clients exit.
In Desktop Mode, Valve fixed a regression that stopped scripts being added with Add to Steam. The beta also carries security and stability updates.
It is a beta, so Valve says the features are still being tested. Owners who want to stay on the stable channel keep SteamOS 3.8 and do not need to change anything.
