SteamOS 3.9.1 Preview and 3.8.27 Beta roll out

Valve shipped two SteamOS testing builds on 14 September: SteamOS 3.8.27 Beta and SteamOS 3.9.1 Preview. Both are opt-in through Settings, then System, then System Update Channel, and the notes for each are unusually explicit about what has been broken.

What 3.9.1 Preview fixes

The headline repair is a system crash when launching Forza Horizon 6 on the Legion Go 2, the Lenovo handheld Valve has been steadily tuning SteamOS for. The preview also corrects frame limits that were producing lower-than-intended frame rates on certain external displays, resolves suspend and resume faults on systems with RDNA1 or RDNA2 dedicated graphics, and mends a regression in seamless boot that was hiding the boot logo before the Steam startup animation.

A fan-control bug carried over from the beta is fixed here too: fan speed could revert to BIOS control until a reboot, leaving cooling louder and faster than intended. Valve has also updated the renderdoc version bundled with the build and fixed verbose-mode boots, triggered by the steamos-bootdebug utility or the chainloader menu, having their output swallowed by plymouth.

The bigger 3.9 changes underneath

Because these notes roll up everything since the stable 3.8 release, the preview also carries the substantial work already delivered in the wider SteamOS 3.9 cycle. That includes an updated Arch Linux base and a Desktop Mode jump from Plasma 6.4.3 to Plasma 6.7.3, an updated bootloader for better compatibility with certain motherboards, and a switch of the WiFi backend to wpa_supplicant by default for new installations, which Valve says improves compatibility with a range of networks and adds fast reconnection on resume from sleep.

Deeper down, the Linux kernel has been rebased on Linux 7.2 with preliminary hibernation support that is not yet exposed in the Game Mode interface, running SteamOS as a virtual machine guest with accelerated graphics has been improved, and a long list of scripts and packages has been renamed from steamos- to holo- with aliases kept for the old names.

SteamOS 3.8.27 Beta, by contrast, contains exactly one change: the same fan-speed fix. Valve's own wording for the preview channel warns that these are early builds which may still contain unexpected bugs or stability issues, and asks anyone who hits one to file it on the SteamOS issue tracker rather than sit on it.

Our opinion

The interesting thing about this pair of releases is not the feature list, it is the shape of it. Valve is now doing the unglamorous work that decides whether SteamOS is a console operating system or a project: fixing suspend and resume on two generations of Radeon graphics, chasing frame-limit behaviour on external displays, and keeping fan curves sane on a handheld that people hold in their hands. None of that makes a trailer. All of it is what a device you actually rely on needs, and the Legion Go 2 crash fix shows Valve is willing to patch for hardware it does not make. The hibernation work is the one to watch, because proper sleep-and-resume is exactly where desktop Linux has historically embarrassed itself on laptops and handhelds. Valve has been shipping these previews at a steady clip without ever calling SteamOS finished, and that restraint is why the platform keeps improving.