your best bet is to get UniVBE6.7 and use it's UniRefresh program, it will detect your card's capabilities and will allow you to set refresh rates in DOS for VBE modes (Duke3D, Blood, Quake use them for example).
Okay, got all that running.
UniVBE seems to take care of whatever FASTVID does, so FASTVID becomes redundant, or so it seems. UniRefresh worked where expected, very nice.
Now... I did a round of totally unscientific testing and found that... Well, my main rig emulates a machine in DOSBox faster than a real P3 and video cards I have here. And that's a bummer.
From those four, the SiS card clobbers the rest in both Doom timedemo and Blood framerate, considering it's the only card on the list on AGP and the only chip with heatsink, I think the comparison is perhaps not fair. 3D Rage card is a distant second and only a hair quicker than the S3 Trio64V+. Rendition card is very very distant last. Just for giggles I fished out a 1988 WDC Paradise 256KB VGA ISA card, and ran the Doom timedemo on it. Pretty even with the Rendition card. Timedemo on Rendition and Paradise were slower than realtime. Again, totally unscientific.
In another totally unscientific test I raised PCI clock and found that S3 Trio64V+ benefits from PCI clock increase much more than ATI 3D Rage, overtaking it by a healthy margin.
DOSBox on my main rig clobbers them all by wide margin. Not good, because I'm not exactly happy with how Blood runs.(a light pun right there)
UniVBE 6.7 I used while increases framerate, also causes severe flickering of weapon and HUD in Blood on S3 Trio64V+. 3D Rage suffers from a different artifact - horizontal stripes on sprites. No artifacts on the SiS card caused by UniVBE. The artifacts I mentioned in first post on the SiS card seems to be caused by AGP timings, I lowered AGP clock to about 55MHz and the few flickering pixels in Doom went away.(only in Doom, and not Blood)