Do you use gamescope on Steam Deck or what? If yes - its very bad way to try Upscale image, image quality too low and gamescope now support only FSR 1.0. I have tried it. FSR 1 to 2 or even 3.1 its a big different at image quality and image details glitches. Usualy gamescope FSR on Steam Deck only allow you run games win 720p with scaled method to 1080p (or for Steam Deck from 480p/540p to 1280x800 (about 720p)). So its upscaling method, BUT, image not upscaling from NATIVE 1280x800 to 1080p. FSR 2-3 what has Upscaling feature allow you run game with NATIVE resolution and scale it from 1280x800 to 1080p or even 2K, to perform Anti-aliasing feature instead MSAA anti-aliasing and has much better image details quality. Build-in game Upscaling is much better and I allow run this feature even on Linux/Steam Deck, where I am from. For example Steam app "Lossless Scaling" not working on Linux machines. I am with my RX 5700 XT very enjoyed image quality and anti-aliasing feature in new games that support FSR 3-3.1, its brilliant boost to my GPU, and has MUCH better anti-aliasing quality as well that usual MSAA, TAA anti-aliasing methods.

UP, its really very needed. It is may do easy and simple game performance boost. I have tested this feature in many games what have already implemented FRS minimum 2.0, its look really cool, even better than at TAA High settings. Game need great and easy performance boost optimization? Just do great improvement with AMD FSR modes: Off, Quality Mode, Balanced Mode, Performance Mode, Ultra Performance Mode, NativeAA Mode. NativeAA mode its super techniche its looks amazing, and I think that its should has higher priority than other optimization in game, because AMD FSR Upscaling + SMAA doing realy SUPER GREAT JOB. Its look amazing. I know at least one game that has implemented this combination, and its look amazing and has much more higher performance than MSAA + SMAA. If its allowed by forum rules, I can leave here name of the game where it is implemented.