Your framerate will improve, a LOT.
I am running a GeForce2 GTS 32mb (in a Duron 1ghz, 256mb PC133)
Running at 1024x768x32bit 4x FSAA and my framerate is a constant 50; it goes down flying thru smoke.
I had a Voodoo5 before but I had awful stuttering. It doesnt happen to everyone but a few people experience it. It happens in AH and a few other games. Its not a Framerate issue, but stuttering. Weird.
As for the FSAA, I did not notice difference between the two cards. Maybe the V5 looks better, but frankly, you really have to squint to notice it.
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Fat DRUNK Bastards.
Nothing feels sweeter than facing a powerful enemy 1 on 1, the battle is tough, but you emerge victorious. As he types <S>!!! on channel one, you open fire on his chute.