So my Pentium III-450 just arrived, and I swapped out the Pentium II and re-benchmarked it on both my cards (and OSes). I also reformatted my results up to now to match the format on the first page.
Here are the 3DFX results on both processors:
35.5 FPS, zerker, 3Dfx Voodoo III 2000 (4.12.01.0666) @ 143.2 MHz, Pentium II 350 @ 349.19 MHz, Intel SE440BX-2 (82440BX), 192MB SDRAM PC100 CL3-2-2, 98SE
38.9 FPS, zerker, 3Dfx Voodoo III 2000 (4.12.01.0666) @ 143.2 MHz, Pentium III 450 @ 448.96 MHz, Intel SE440BX-2 (82440BX), 192MB SDRAM PC100 CL3-2-2, 98SE
Next for the GeForce 2 MX. Didn't retest Win98 + GeForce on the Pentium III because I don't actually want to keep Windows 98 drivers enabled for this card. Last time I reverted to a backup after testing, which isn't my preference.
48.6 FPS, zerker, ABIT Siluro GeForce 2 MX-400 (81.98) @ 100/182.55 MHz, Pentium II 350 @ 349.19 MHz, Intel SE440BX-2 (82440BX), 192MB SDRAM PC100 CL3-2-2, 98SE
45.2 FPS, zerker, ABIT Siluro GeForce 2 MX-400 (93.71) @ 100/182.55, Pentium II 350 @ 349.19 MHz, Intel SE440BX-2 (82440BX), 192MB SDRAM PC100 CL3-2-2, XP-SP2
51.0 FPS, zerker, ABIT Siluro GeForce 2 MX-400 (93.71) @ 100/182.55 MHz, Pentium III 450 @ 448.96 MHz, Intel SE440BX-2 (82440BX), 192MB SDRAM PC100 CL3-2-2, XP-SP2
Incidentally, can anyone recommend a Windows-XP tool for grabbing the clock speed of a Video card? The Windows 98 tool I already had just bluescreens on Windows XP, and CPU-Z could supposedly grab that information, but is just blank for me right now (hence the TBCs above).