SteamOS 3.9 Main now boots on Intel Arc B580 without workarounds, 1440p gaming tested

Direct boot without workarounds

Previously, using a discrete Intel GPU with SteamOS required installing an older system version, updating it, and then swapping the card for an Arc model. The new SteamOS 3.9 Main build used in testing allows the system to boot directly with an installed Intel Arc B580 card. This simplifies setup for Intel hardware users.

It is important to note that testing was performed using a version from Valve's Main development branch, not the current public Beta channel. Support for Intel GPUs in SteamOS was added in version 3.8.25 (e.g., for MSI Claw 8 EX AI+), and this same development branch is currently being used.

Performance at 1440p

The test configuration included a Intel Arc B580 with 12GB of memory and a Core Ultra 5 250K Plus processor. Results at 1440p are as follows:

• Cyberpunk 2077: reached the mid-70 FPS range at 1440p High using XeSS Quality.
• Horizon Zero Dawn Remastered: ran in the mid-60 FPS range at 1440p High with XeSS Balanced.
• Fallout 4 and Elden Ring: both games ran at 60 FPS at 1440p, with Elden Ring using maximum settings without upscaling.
• Forza Horizon 6: averaged around 74 FPS at 1440p High without scaling.

The system demonstrated stable performance above the 60 FPS threshold, although occasional dips were observed. Performance under Windows in similar scenarios was slightly higher (e.g., around 85 FPS in Forza Horizon 6).

XeSS limitations on Linux

Despite successful system booting, using Intel acceleration technologies under Linux is currently limited. The Intel Arc B580 GPU features dedicated XMX engines, but the current open-source Linux driver path does not expose them for XeSS acceleration.

XeSS still runs through its shader-based fallback path, but image quality is lower than in Windows. Also unavailable are XeSS Frame Generation and Multiframe Generation. Intel's current XeSS Frame Generation documentation lists Windows 10/11 and DirectX 12 as requirements, so these features do not work under Linux yet. The remaining option is FSR Frame Generation.

Direct boot support in SteamOS removes one of the major barriers for using Intel Arc GPUs, but driver functionality still lags behind the Windows version.