the 470 and the 480 has been discontinued prior to the release of the 580 and 570. if your wondering about the diffrences in them go to
www.nvidia.com and find them under products and compare the details, theres just more in clock speeds in the 500s then the 400s they both use the same new chipset. there isn't too much of a diffrence but the 500 series do make an impact. i wouldn't recomend buying the 580 superclocked based on their price. you come out way better (if you plan to spend it) buying two 570s which will run you about $200 more but will out-perform a single 580 superclocked or not. but in anycase if your mother board isn't compatible with sli then go with what you want in the end. 500 series cards are excellent cards and most of the time these are the performance jumps you will see with these cards. i recently had 3 9800 gtx+ 512s in 3-way and didn't even come close to the performance i get with two 570s and way quieter and cooler. so if any of are thinking of buying them. they are worth it.
