Yeah this is a tuffy. I too had the same idea as vlask but was concentrating on the cards of 1997, which I was benchmarking 12 different chipsets.
Biggest problem is drivers, what good is a benchmark number if you have crazy artifacts and glitches that would pretty much make the game unplayable. So now you are going to have to make screen shots too. 😜
MDK is a great benchmark, runs in DOS, Win 2D and Win D3D. It even runs on my Win7 system with a score of 1250, which is only 4-5 times faster then a Pentium with Voodoo1. 😕 Also have to run with V-sync disabled to get a score greater then 250. May run into driver issues here with earlier cards.
Turok is another good one, with it's built in benchmarking tool. To be fair you will have to turn all settings on, which is going to make many earlier cards sad and ugly.
Another one that was said earlier too is MotoRacer, but it's benchmark is in real time while you drive around. You pretty much have to start a race and not do anything as the cycles drive off and record your framerate to get anything consistent. It does work well with anything you throw at it, from #9 Revolution 3D to a Matrox Mystique 220.
There is a stand alone Forsaken benchmark out there, with D3D, Glide and PowerVR built in. It plays a prerecorded rolling demo with a plethora of settings. Here comes the hard part, do you run all cards in D3D to be fair, or run the Voodoos in Glide and let it look better and run faster? Guess you have to run it both ways!
I like Final Reality, but you may run into driver issues.
There's Ziff Davis 3D Winbench 97 and 98. I don't really care for those, I like real world game benchmarks better. It was somewhact popular at the time though.
Another you might try is the X3TC rolling demo, I think it's D3D exclusive. From 97' I think, in space.
Good luck!