My experience with the Rage family is that they have terrible dithering effects on surfaces. Is this just the games I've played or did I have an old 16 bit color only board?
I've never had a good opinion of the Rage series.
Nearly all the old video cards have very visible (relatively simple/odered) dither patterns in 16-bit colordepth, the exception would be those lacking that feature entirely (I think the Voodoo1 can't dither at all) or games specifically disabling that feature for other cards. (Playstation and N64 do it too -though N64 has more advanced dither patterns, as do later PC GPUs)
Dithering was used to add smoother shading to limited colordepth and is absent (almost always) in 24/32-bit color. (this is also different from the stipple/dither mesh "transparency" effects used by the Matrox Mistique and a few other cards and software renderers -those are simple meshes with "holes" left in them for transparency, dithered interpolation OTOH adds dithered patterns to approximate blending in higher colordepth for both shading and blending)
The old Rage series (I/II//Pro) wasn't the best at dithering (like most early cards, limited to relatively simple patterns), but some were actually worse. I believe the RIVA-128 was regarded as uglier in this respect (though it has other visual advantages over the RAGE) and the S3 ViRGE cards have some additional dither artifact issues on alpha textures. (odd mattes/boarders/halos, though more of a blending artifact than dither-related -it's also not there in 24/32-bit color modes)
But to the point here with the Rage 128: this shouldn't be a problem for any games supporting 32-bit color (which should perform quite well on the RAGE 128 Pro) and I believe the dithering in 16-bit color is a bit better than the original Rage cards as well. (plus, most/all later D3D/OpenGL games have detail options allowing dithering to be disabled entirely, at the expense of heavier banding/posterization native to 16-bit color)
Some cards definitely have noisier 16bit dithering. Riva 128 is the most intense I've seen personally.
Rage 128 got complaints for grainy 16bit dithering though. The Pro revision improved this aspect. Of course you can just use 32bit color instead.
This problem wasn't really solved (for 16-bit renderers) until error-diffused dithering was introduced around the time of the early Radeon/Geforce cards, right? (ganted, you're always going to get some graininess, but ordered/pattern dithering has a much more obvious "digitized" grid or crosshatch look while diffused dithering is more organic/natural/analog looking -more like grainy film or noisy analog video)
And again, any game supporting an option for no-dithering in 16-bit color will also avoid that problem at the expense of heavier banding/posterization. (which could be preferable for some games -especially at lower resolutions) Then-again, most games supporting that will also probably have an option for truecolor rendering, which would be preferred in general.