If anyone is interested, I finally found access to a 5080 and 5090 for speed testing.
Looks like the 5080 is about 3,850 Mk/s and the 5090 is about 6,650 Mk/s
Comparing to a 4090 at about 4,500 Mk/s its about a 47% increase in KeyHunt.
I haven't tried other grid sizes, but both are only using about 50% of the VRAM with the auto grid.
Start Time : Tue Feb 18 03:28:22 2025
Global range : 000000000000000000000000000000000000000000000000000000B1D37A781F (40 bit)
GPU : GPU #0 NVIDIA GeForce RTX 5090 (170x0 cores) Grid(1360x128)
[00:00:04] [GPU: 6683.80 Mk/s] [C: 3.50 %] [T: 26,738,688,000 (35 bit)] [Puzzle: 67] [Shares: 1365.47 ] [EST Payment: 0.007000 BTC] [Searched: 0.015941 %]
[00:00:06] [GPU: 6654.08 Mk/s] [C: 5.23 %] [T: 39,929,774,080 (36 bit)] [Puzzle: 67] [Shares: 1365.47 ] [EST Payment: 0.007000 BTC] [Searched: 0.015941 %]
Start Time : Tue Feb 18 03:53:11 2025
Global range : 000000000000000000000000000000000000000000000000000000631E19728C (39 bit)
GPU : GPU #0 NVIDIA GeForce RTX 5080 (84x0 cores) Grid(672x128)
[00:00:04] [GPU: 3875.17 Mk/s] [C: 3.64 %] [T: 15,502,147,584 (34 bit)] [Puzzle: 67] [Shares: 1303.03 ] [EST Payment: 0.006672 BTC] [Searched: 0.015960 %]
[00:00:06] [GPU: 3816.42 Mk/s] [C: 5.38 %] [T: 22,900,899,840 (35 bit)] [Puzzle: 67] [Shares: 1303.03 ] [EST Payment: 0.006672 BTC] [Searched: 0.015960 %]