my experience when trying out this s3 savage4 pro card out on a 98se install with stock dx6.1a: with the august 2000 drivers everything seemed to install fine at first, but then i quickly realized that 3d acceleration isn't available and this 16mb card is detected as 1mb in dxdiag. also dxspeed gave some really weird number for the page flipping around 550 when it should be just matching the monitor refresh rate. given the driver date i decided to try installing dx7 and sure enough, that fixed it and gave higher throughput in dxspeed with the page flipping score matching as well. so while there's no documentation whatsoever for that driver clearly it's designed around at least dx7, which isn't entirely unsurprising given the driver date.

the thing is though, i definitely recall reading more than one post here suggesting to just stick with dx7 for nvidia with 98se even with much later post-dx9 era drivers, and while that's indeed doable, i'm now wondering if some driver inconsistencies i've experienced there could be due to a mismatching directx version. on the ati side though, for one the rage 128 cards can be really finicky with this - the latest drivers won't even install without dx8 period. i know the "boring" solution is to just throw dx9.0c on every build, and that's what i used to do myself, but really there's otherwise no reason to do so considering how badly those dx8 and 9 games would run on such old cards anyway.

i think dxcapsviewer has been posted in an older thread here but it's a newer version that doesn't run under 9x (or pre-dx9). maybe someone has an older version of that tool, which could perhaps be useful to see what dx version a driver was actually written for?