Riva TNT2 M64 or Voodoo4 4500? Help Please...

Hi,
I have a computer that is of the following spec: Duron 700Mhz and 256mb
Pc133 Ram. The computer sadly only has a 2x AGP port. Now i have two
graphics cards:

Nvidia Riva TNT2 M64 AGP
3DFX Voodoo4 4500 AGP

I want the machine to be used for game playing (this computer is a spare
computer i have put together) Which of the above graphcis cards do you think
i shoudl use in the machine. I obviously want the best compatability with
good/latest games - and obviously the maximum performance i can push from
the system. If you have any of these cards could you please also advise on
any 'Top Performing' Drivers.
I am using Windows XP Professional on the system,

Thanking you in advance,

Ben Nealon

P.S - Do most recent-ish games not supprt the 3DFX Chipset anymore?