Agp gfx card

which would be better
ATI Radeon X1600 Pro 512MB 128 Bit Dual Link DVI-I HDTV-Out AGP Graphics Card
BFG GeForce 7600GS OC 512MB AGP
[COLOR=black]BFG GeForce 6800 GS OC / 256MB GDDR3 / AGP 8x / DVI / VGA / TV Out / Video Card[/COLOR]
or is there anything else around 200? that is better?
or would it be better to add another 1 gig stick to my 1gig stick …