The pci express wouldn't have any advantage over an agp card. With that
old of a game, any decent card should work fine. Granted, I don't claim
to be a professional at this, but it won't matter if you get pci express
or agp, it just depends on what your motherboard supports. I'd recommend
grabbing a pci express card, however, only for the fact that it will
probably be easier to upgrade later on down the road, agp cards seem to
be dying out.