the 9800 GX2 will have the most performance (3-4 times the other cards)
but you don't just video card performance by the amount of video ram they have, the core clock and memory bandwidth ans speed are far more important.
Go to tinypic (dot com) and upload it on there.
take the first link they give you, i think its called "html" code, and paste it into your about me or wherever you want it.