Wow I just discovered this section.
Let's post our Q3 results !!!!!!!  
Stick to 1024x768 and DEMO 1/Quake 3 Unpatched if you can.

System :
Aopen AX3S mobo, Pentium III 1ghz, 256 PC-133, Voodoo 5 agp bios 1.18 with the last 3dfx beta drivers, Windows 98se, SB 128, HD 80 gig IDE 133 Maxtor 7200 rpm.
Gameport Disabled on the soundcard.

Here's my result :

Quake 3 1024x768 all visual settings at max, sound at low Q.
Demo 1 at 16 bits textures + colors 94.1 fps
Demo 1 at 32 bits                   71.3 fps

Same test and system, except P III 800 mhz instead of PIII 1 ghz
Quake 3 1024x768 all visual settings at max, sound at low Q.
Demo 1 at 16 bits textures + colors 87.3 fps
Demo 1 at 32 bits                   69.9 fps

Update : the small increased going from PIII 800mhz to 1ghz
is explained by the saturation of the Voodoo5 fillrate at 1024reso+32bits.
Going with an even more powerfull CPU at these settings will produce marginal increase. However at 16 bits and lower resolution, the V5 will have better scaling.

Update no 2 : I have replace my soundcard, the SB 128 was changed for a SB Live. The result are identical, or very tiny boost in favor of the Live and the sound quality is a lot better on the Live.

@Steph3dfx,

Your results are with Quake III patched to 1.32 and using time demo FOUR.DM_68 ?