SteamOS 3.8.0 Preview is another big upgrade for Valve's Linux distribution, with lots of enhancements to hardware support across the board for handhelds. This also includes initial support for the Steam Machine, not that any of us actually has one yet but Valve are clearly working towards getting everything ready for it.
You'll also see an updated Arch Linux system base, with an improved graphics driver, improvements to VRR and lots more. This is in the Preview channel available via Settings > System > System Update Channel.

Here's everything that's included in it (changelog):
Known Issue: Users not currently opted into Preview channel updates may be automatically returned to the Beta channel when attempting to opt-in. This can be worked around by enabling "Advanced Update Channels" in developer settings, and will be fixed in an upcoming Steam Client update.
General
Initial support for upcoming Steam Machine hardware
Updated Arch system base
Updated graphics driver with performance and stability fixes
Fix a case where per-app performance settings would intermittently fail to apply when launching a game
Improved support for the screencasts in Game Mode (e.g. OBS/Discord)
Fixed dropdown menus not appearing in some games
Improved VRR frame pacing
Fixed FSR badge remaining off in the performance overlay, even if it was actually active
Improved support for games that attempt to open PDF files in external viewers
Fixed an issue affecting certain titles (such as "SpongeBob SquarePants: Titans of the Tide") where the game window could have an incorrect position
Fixed closing certain titles (such as "STAR WARS Jedi: Survivor™") and Starfield resulting in a session crash
Improved support for certain USB racing wheels and USB devices that boot in a non-standard mode
Frequently these are devices that appear as USB storage devices with a driver installer, and must be switched to their normal mode by the OS
Steam Deck controller firmware updates now display update progress on the splash screen
Fixes issue on specific Steam Deck revisions where firmware updates could render the left controller inoperative for that session
Numerous stability and security updates
Bluetooth
Re-re-enable Bluetooth Wake for Steam Deck LCD
Fix for more spurious wake issues that were present in earlier attempts
Audio
Detect HDMI channel count and expose surround configuration if available
Add a setting to allow using Bluetooth headset mics (Bluetooth playback quality will be worse while capture is active)
Restore internal audio device on reboot if set to "Off" in desktop mode
Increase suspend timeout for HDMI devices so initial audio isn't cut off after a few seconds of inactivity
Fixed a bug with switching input devices when a wired headset is plugged in
Fixed an issue where audio underruns could be experienced after sleep/resume
Accessibility
Added an option to force mono audio output
Desktop Mode
KDE Plasma updated to version 6.4.3 from 6.2.5, and now uses wayland by default
Fixes several cases of reduced performance in Desktop Mode compared to Game Mode
Improved support for rotated displays
Better scale factor out of the box on TVs
Adds support for external HDR displays
Adds support for VRR displays
Adds support per-display scale factor
For more information, see Plasma release announcements
Keyboard layout and language are now obeying Game Mode settings
Improved windowing behavior for games running in Proton
System Firmware
Includes Steam Deck LCD BIOS v133
Security updates
Added "Memory Power Down" setup option
Preliminary support for hibernation
Includes Steam Deck OLED BIOS v114
Security updates
Charging LED now changes color when charge limit is reached, rather than only at 100%
Non-Deck
Improved compatibility with recent Intel and AMD platforms
Greatly improved video memory management with discrete GPU platforms
Fixed a compatibility issue with the SteamOS chainloader that could cause a boot failure on some desktop systems with recent UEFI firmware
Power button short and long presses now supported across a wide variety of devices
Improved controller support for OneXPlayer F1 series, GPD Win 5, GPD Win Mini, Anbernic Win600, OrangePi NEO, and Lenovo Legion Go
Added controller support for OneXPlayer X1 series and Lenovo Legion Go 2
Added system and controller firmware update support for the Lenovo Legion Go 2
Added preliminary charge limiting support for Legion Go, Legion Go S, and Legion Go 2 - currently only accessible in Desktop Mode
Added controller RGB LED color settings for the Lenovo Legion Go 2
Added controller, TDP control, and speaker audio support for the ASUS ROG Xbox Ally series
Reduced handheld controller input latency from 5-8ms to 100-500us
Night mode, color vibrance, and color temperature sliders in Steam now work on Z2E and later AMD APUs
Seamless boot fixes for Z2E and later AMD APUs
Automatically handle internally rotated display for some third-party handhelds
Improved motion control support for handhelds with BMI260 IMUs
SD card reliability improvements for some third-party handhelds, including ASUS ROG Xbox Ally, Legion Go 1, Legion Go S, Legion Go 2, and MSI Claw
Fixed washed out colors for Zotac and OneXPlayer handhelds with OLED
Fixed some GPU hangs on Phoenix APU devices (Tales of Arise, Octopath Traveler II)
Fixed ASUS ROG Ally power consumption from fingerprint reader while shut down
Developer
Desktop Mode now uses Wayland by default
X11 support may still be selected via Steam developer settings, or via `steamosctl`
Updated Linux kernel to 6.16
Steam now uses steamos-manager to query available desktop sessions and trigger desktop session switching
Added support for setting the desktop password in developer settings
Initial support for running as a Virtual Machine guest (virtio guest drivers)
Added support for third-party devices to trigger the SteamOS boot menu via EFI variable
Added `custom-update` verb to `atomupd-manager` for easier testing of specific builds
System reports now include more audio debug information
Initial support for LAVD CPU scheduler via `steamosctl set-cpu-scheduler lavd`
There was also a Steam Deck Beta Client update that includes (changelog):
General
Added a setting to enable 'Switch To Desktop' in the login screen. It can be found in Settings > Interface.
Fixed a case where opting into the 'Preview' channel could silently fail.
Chat
Moved Steam chat into the quick access menu, making it easier to access while in-game.
Introduced new quick chat feature for Steam Deck and Big Picture Mode
When in a chat, press and hold the view button to bring up quick chat options.
Move thumbstick and release view button to send a quick chat.
Quick chats can be edited in Settings > Keyboard
Focus will no longer jump to room effect replay buttons when scrolling through chat history
Fixed a bug that would sometimes prevent chat history from loading when scrolling up
Do leave a comment and let me know what you think to this update if you're testing it. Really great to see some big improvements!
Re-re-enable Bluetooth Wake for Steam Deck LCDHopefully that will stay enabled for some time as it's annoying issue if the Steam Deck is connected to TV most of the time.
Re-re-enable Bluetooth Wake for Steam Deck LCDSo…they enabled it, disabled it, re-enabled it, disabled it again, and are now re-enabling it for the second time? 🥴




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