Valve Ships SteamOS 3.9 Preview With Linux 7.2 Kernel and KDE Plasma 6.7 — BigGo Finance

Valve has pushed out the first preview build of SteamOS 3.9, bringing a significantly refreshed software stack to the Steam Deck and other supported hardware. The update, released late Thursday, moves the operating system to the Linux 7.2 stable kernel and upgrades the desktop environment to KDE Plasma 6.7.3, replacing the older Plasma 6.4.3 that had been shipping on the platform.

The jump to Linux 7.2 is notable for what it unlocks under the hood. Valve says the newer kernel delivers expanded hardware support, improved performance, and other refinements over the Linux 6.16 LTS base that SteamOS had been using. Desktop Mode users, meanwhile, should notice fewer bugs and a generally smoother experience thanks to the Plasma 6.7.3 update, which incorporates a long list of fixes accumulated since the previous version.

Beyond the headline kernel and desktop changes, the preview introduces several under-the-hood improvements. SteamOS 3.9 switches to WPA_Supplicant for more robust WiFi handling, adds preliminary support for system hibernation — though it is not yet exposed through the Game Mode interface — and improves the experience of running SteamOS as a guest virtual machine with VirtIO graphics acceleration. The Arch Linux package base has also been refreshed as part of the update.

Valve is positioning this as an early preview, meaning users on the Preview channel will get first crack at the new software before it graduates to Beta and eventually Stable. The company has not provided a timeline for when SteamOS 3.9 will reach the Stable channel, but the preview release suggests the development cycle is well underway.

The 3.9 preview arrives as Valve continues to refine the current stable branch in parallel. Earlier this week, the company released SteamOS Beta 3.8.26, a maintenance update focused on fixing issues found in previous beta builds. That release addressed a performance regression that could occur when composition was required, such as when using FSR, and worked around a problem that caused Unreal Engine 5 VR titles to display a blank image in the right eye.

The beta update also tackled hardware-specific problems on third-party handheld PCs. A Wi-Fi issue affecting the MSI Claw A1M was fixed, as were battery display problems on Lenovo Legion Go models. Another fix prevents the MSI Claw from freezing when resuming from sleep with an SD card inserted. Bluetooth instability affecting the Nintendo Switch Pro Controller (v1) was also addressed.

For users deciding between channels, the two updates serve different purposes. The 3.8.26 beta is a stabilization release aimed at making the current feature set more reliable, while the 3.9 preview represents the next major step forward for the platform. Valve typically keeps multiple branches active simultaneously, allowing it to ship urgent fixes to stable users while testing larger changes in preview and beta channels.

The SteamOS 3.9 preview is available now through the system update settings on Steam Deck and other supported devices, provided the user has opted into the Preview channel. Valve has published the full changelog on its Steam community forums for those who want to review the complete list of changes before installing.