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AMD's FSR 4 is by far the best upscaler the company has ever produced, but is it coming to the Steam Machine? We asked Steam OS developer Pierre-Loup Griffais and he confirmed that FSR 4 is indeed on the way - but it won't quite be ready for launch.
Even that qualified statement is quite a relief, given that AMD has gone back and forth on whether FSR 4 was a feature exclusive to Radeon 9000 series GPUs. That was the party line when the tech was first shipped - even as a leaked INT8 version was making the rounds with support for older architectures. Team Red finally announced an official July release window for Radeon 7000 back in May, though support for RDNA 3.5 is still officially doubtful.
FSR 3 can be quite heavy on the Steam Machine, to the point where targeting a 1440p output resolution can see you being CPU-limited - which isn't ideal for ensuring a stable frame-rate. FSR 4 ought to improve things, as while it is marginally more expensive, its quality is much better - so you can get away with using a lower internal resolution that runs faster while enjoying similar or better image quality overall.
Pierre-Loup mentioned that while Valve has been working with AMD to bring FSR 4 to Steam Machine, the final release time frame isn't yet confirmed:
"We don't have a time-frame to share with you, but we're excited that it's coming through on the same schedule... Any game that supports the FSR SDK with a new enough version that it has the upgrade path within the AMD software will just light up, and the FSR option will just start using FSR 4 when Proton rolls out support for it."
That implies that it should be available next month, or at least at the same time as the eventual Windows release, and that it will be handled in a similar way to on Windows where the DLL is automatically upgraded with no special fiddling (and no involvement by the developers).
Currently, using FSR 4 is quite a manual process on Linux, requiring some additional Steam launch commands, so we'll be fascinated to see whether Valve and AMD are able to provide a more streamlined alternative.