Hey guys im looking to upgrade my cousins computer with some more ram. He has 2 512 sticks of ddr 400 ram. He only has 2 slots for ram and I was wondering if taking out 1 stick of 512 and replacing it with a 1 gig stick would be worth it? Or for some actual results in preformance should I take out both 512 sticks and put in 2 1 gig sticks? Would replacing only 1 512 with 1 gig ram still give a good speed increase or is it worth the extra 39 dollars to get another stick?