Actually, I'm quite sure about the 512x384 resolution thing - I remember it well because that's the only resolution at which my good old P2 350 with 256 MB of RAM would run Unreal 1 smoothly. Maybe it had something to do with my monitor's supported resolution modes? As the the Riva TNT being more powerul, well 5 mins of Google and I can't find any old benchmarks and reviews, so I hope I'm right :)