patch; they are extra rasterizing dll's that add to your gpl directory.
From within the game options screen you can then choose which one you want
to use. Of course you'll need to exit the game and load it again in order
for the new chosen driver to spring into action. Just go ahead and try and
test both.
Sorry I can't give an anticipation as to what the results are (I haven't
succeded in putting either into work but I wasn't expecting much here: I'm
using a Rendition V2200 and/or Voodoo1)...
Cheers,
Rui