There are plenty of other people on the message board talking about how wonderful this is, but I can't back up their results. I did see the device name go from "3dfx Voodoo Series" to "3dfxVoodoo5" as described in the article, but my performance didn't really improve.
I did see what I thought was a substantial performance difference, going from 54.1 fps to 68.9 fps in Quake 3. I quickly discovered, however, that the increase had come from the drivers resetting to their defaults and turning off 2X FSAA. Turning it back on dropped my frame rate back to 54.2.
I'm not certain if the people talking about how wonderful it is are just going on subjective opinions, or if they made the same mistake I did and didn't realize FSAA was turned off? If anybody out there has tried this tip and seen an increase in performance from it, please comment on this.