Try checking on the manufacturers website:
http://www.diamondmm.com/support.php
If no luck there, then try here:
http://www.voodoofiles.com/3dfxhelp.asp
(They are currently undergoing construction so check back later.)
Your graphics board contains one of the last chipsets that 3DFX ever made... the Voodoo II. It's a shame they went out of business quite some time ago.