I don't know how things run on a P3, but with a K6-3 running Win98 with a Geforce2 MX and MVP3 chipset, nVidia drivers 8.05 and 12.41 both perform well. It's been a long time since I was experimenting with this but I think 8.05 was emerging as my favorite for that system.
I was running a bunch of tests, then finding fault with my tests and redoing things and then just got fatigued with the whole project and haven't touched it in probably a year now.
Some later versions that I've tried (21.81, 21.83, 45.23) are extraordinarily slow in some games. So is v6.31 for whatever reason (v5.32 is fine).
There are some weird performance variations between games and drivers on the K6-3, but that might be a CPU optimization issue so the P3 might like different versions than the K6 does.
I've never needed to use later drivers to fix anything I tried to play. Even v5.32 runs anything as far as I can tell, and it was my preferred version back in those days (I now think 8.05 is probably better though).
So I think the best versions are going to fall into the time period when nVidia was optimizing the most for your hardware. Game compatibility is rarely an issue IMO.
If nVidia's Win98-era performance on a P3 is as erratic as it is with the K6-3, then you may need to experiment with the games you actually want to play (not synthetic benchmarks).