Not just Optiscaler, now DLSS Swapper can also replace FSR 3.1 with FSR 4 for superior visual quality in FSR 3.1-supported games.

Replacing FSR 3.1 DLL Files With FSR 4 DLLs Reportedly Works; Developer Says It Didn't Expect It To Work

AMD's FidelityFX Super Resolution 4, aka FSR 4, is currently one of the most refined versions of AMD's upscaling feature for RDNA 4 GPUs. To enable the FSR 4, the games need to support it officially, and it has to be integrated by the developers into the game engine. There aren't a lot of games that currently support FSR 4 natively, but there is a workaround through which gamers can enable FSR 4 by replacing older FSR versions.

Many gamers use tools like Optiscaler and DLSS Swapper to swap older versions of upscaling technologies such as DLSS, XeSS, and FS

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