I have 4 gigs. Thats 2x 2 1 gig sticks. Also I should go with upgrading my CPU rather then a graphics card? Have a HD 4870 1gig which does pretty good for the most part. Huge gamer and I have heard quads are not really important for gaming still at the moment
Upgrading the VGA will give you more boost in performance because almost all games are GPU limited.