Nvidia drivers slowing down - Retrospective Windows 98 GPU and driver benchmarks

I've rewatched Phils's "Retrospective Windows 98 GPU and driver benchmarks" video again today, where he tested Win98 game performance with various Nvidia architectures from TNT up to FX series, with the conclusion being that you'd probably be better off with GF3/GF4 cards if you value highest possible framerate (at pretty much any resolution), mostly due to the fact that you can use earlier, better optimized drivers with these cards.
There's one caveat though - the test system was based around a Slot1 P3 1000 system... I would naturally assume that I would be able to compensate the driver disadvantage if I get rid of the obvious CPU bottleneck. Can I exspect to pull a FX5900 Ultra out of it's nvidia driver hole with say, an Athlon64 FX or some Core 2 processor, and have it perform about on par with a GF3 Ti 500 (while also adding some additional eye candy features)? I do want to achieve high framerates, otherwise I'm not really using my CRT to it's advantage. I'm going to stick to resolutions up to 1024 x 768.