RTX 5090 benchmarks showing only minor ~2 second improvement per image for non-FP4 models over the 4090.
https://youtu.be/Q82tQJyJwgk?si=EWnH_SgsLf1Oyx9o&t=1043
For FP4 models the performance increase is close to 5 seconds improvement per image, but there is significant quality loss.