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.
Framegen is worse the lower your base frame rate is.
The penalty to the speed at which the game runs is much more significant, if you normally run at 40 fps and framegen gives you 60 (30 real) then you have introduced 8 ms of latency just from that. While the same 25% performance cost going from 180 fps to 270 (135 real) adds just 2 ms.
The lower your real frame rate is the harder it will be to interpolate between frames because the changes between frames are much larger, so it will look worse. Also the lower your frame rate the longer any mishaps will remain on screen, making them more apparent.
True, Ig I was trying to teach people about why FSR often causes input lag. If you are getting 120 real frames then yeah, it probably won’t matter much, but if you are getting less then 60 real frames it’s going to be a worse experience unless you are playing menu games or something.
Yeah I just wanted to illustrate that with some numbers :)
It’s a bit counter-intuitive that frame generation is worse the lower your base frame rate is. And Nvidia in particular has no interest in making it clear that this tool is only really good for making a well-running game run even better, and is not going to give your 5070 “4090 performance” in any meaningful way.