I was trying out FSR4 on my RX 6800 XT, Fedora 42. Works really well and it easily beats FSR3 in visuals even on Performance. It does have a significant performance hit vs FSR3 though but it still works out to be a bit faster than a native rendering on Quality.
Neat!
I didnt know RDNA2 would work with FSR4 too.
With the Int8 model this should work on older cardd as well as on NVIDIA and Intel