We all know that the 3Dfx is gone,but I don't know why
the closed their  business and left us (voodoo card owners) in pitch dark .
For WinXP/2000 there are few drivers and these  drivers
are not the original (not all of them )3dfx  drivers (original beats everything).
Also I searched the web and found only glide and opengl
drivers for winxp/2000.
I haven't found a voodoo2  D3D HAL  driver for winxp.
For win 2000 I found one but there was a display driver
not a voodoo2 3D accelerator driver(I try it and was bad)
So ,in conclusion when  someone will create voodoo
drivers  (glide+opengl+D3D and DirectX 8.1,9.a,9b,9c)  , for all voodoo cards and this drivers will be  100% good  for winxp/win2003 operating system ? (I wonder ?)

I've heard that Nvidia had bought a part of 3dfx technology,and some of the nvidia chipsets base oneself on the voodoo chipsets.So ,Nvidia could offer technical support for voodoo owners.But they don't do it .Why ?

to answer the original question,standard voodoo2 drivers for win2000/xp will only give you glide and opengl.D3D is not available.this is micro$ofts fault,because they havent implemented support for addon accelerators (like voodoo2) in the winnt kernel.there is one experimental driver that will give you D3D under xp,but its still in alpha state.you can get it here:
http://voodoomage.uw.hu/indexeng.html
be warned,the driver an unstable alpha,contains no uninstaller and can screw up your system seriously.you have been warned.