I ran across this video and am a bit puzzled by the portion with Unreal (or at least the castle flyby demo) running with what looks like proper lighting effects.

https://www.youtube.com/watch?v=wXKMxNg-_0Y

At 22:27 they show Unreal running, and not with the typical broken/missing light maps and opaque/black-rectangle alpha textures early video cards usually run into (if they run accelerated at all). The perspective correction also looks too good for the Rage, regardless of speed. In 320x200 at 23:30 I can clearly see dithering typical of highcolor rendering, but not software mode style dithering, plus they mention it's running much slower than software mode.

I believe that's the channel associated with Putas's vintage3D website, so I searched for more details and mentions in previous vogons discussions, but I couldn't find any references to what's going on here.

My first thought is this is running in OpenGL mode and has fallen back to brute-force CPU OpenGL rendering (which is really slow, but if they're using a Pentium III class CPU, that might make sense here). I ran into this when trying to get OpenGL patched Unreal Gold running on a Riva 128 and Rage Pro around 10 years ago, and kept running into it wanting to drop to software OpenGL (which was something like less than .5 FPS on a K6-300 or Pentium MMX 200), I stopped playing around with that before getting into driver hunting and manually adding DLL files so never got to actually trying OpenGL on those mid 90s GPUs. However, I also remembered not being able to use lower than 640x480 resolution in OpenGL mode, but I may be remembering wrong there. I seem to recall OpenGL still using dithering in 16-bit color mode when software rendering like this. I forget if reflections were broken/missing, but that's a possibility as well and would match what's seen in the video.

Given the Rage I (supposedly) lacks Z-buffer support, that would also preclude it from initializing at all for D3D Unreal, so I assume that's another reason they'd go with OpenGL (though it's not mentioned in the video).

But on the note of Z-buffering, it's also really weird that Half Life is showing Z-fighting errors when there shouldn't be hardware z-buffering being used. Normally, you'd get flickering polygons or pop-in weirdness for per-polygon z-sorting and nothing resembling z-fighting. See Half-Life at 16:00

They don't mention if HL is running in D3D or OpenGL, either.

Given Final Reality wouldn't run at all, either, I'd be rather surprised if anything D3D 6.0 or higher would work on the Rage, unless there's something else weird preventing it from working in this case, given Final Reality is DirectX 5 and often works with GPUs with incomplete feature sets and associated rendering errors/issues, like the Virge 325, even with 2MB. Unless it's 2 MB combined with lack of paletized texture support that's a problem, except I was pretty sure the Virge 325 was very limited in its 256 color palettized texture use as well, and possibly was omitted/disabled for direct3D use. (like a big chunk of features couldn't be used on palettized textures, though I think gouraud shading and z-fogging were still supported; and I remember enabling/disabling 256 color textures in Tomb Raider II didn't help at all with missing textures)