SteamOS 3.9 reaches all users with lower Steam Deck idle power use

SteamOS 3.9 is now available on the stable channel, bringing lower idle power consumption to Steam Deck when no audio is playing. Valve's update also fixes streaming and display problems across SteamOS devices, including Steam Machine.

Steam Deck product imagery supplied by Valve. Image: Valve

The release is numbered 3.9.5 and is available to all users, according to Valve's announcement. Its change list brings together the improvements tested since the previous 3.8 stable version.

Steam Deck gets an updated desktop alongside the power improvement

Desktop Mode moves from KDE Plasma 6.4.3 to 6.7.3, while the underlying system receives an updated Arch Linux base and Linux 7.2 kernel. Valve also fixes hidden Wi-Fi networks failing to connect on the first attempt.

Steam Deck product imagery supplied by Valve. Image: Valve

The power change concerns idle operation without audio. Valve provides no percentage saving or extra battery-runtime figure, so it should not be read as a measured improvement to battery life while gaming.

Hibernation remains unfinished. Preliminary support is included, but there is no Game Mode interface for it, and an outstanding driver bug keeps it disabled on Steam Deck. That limitation follows the earlier beta suspension of Deck hibernation.

Steam Deck product imagery supplied by Valve. Image: Valve

Steam Machine streaming fixes also reach the stable channel

Remote Play should now work when Steam Machine boots without an external display attached. Valve also fixes the frame limiter being incorrectly applied to VR games streamed from Steam Machine to Steam Frame.

Other display fixes address the frame-limiter toggle not working with variable refresh rate and lower-than-requested frame rates on certain external displays. These are specific corrections, rather than a promise that every game will run faster.

The update also resolves a Forza Horizon 6 system crash on Legion Go 2 and adds preliminary brightness-control support for that handheld. Steam Deck owners can obtain the stable release without opting into the Beta or Preview channels.