hi i have a presario s5223wm, i would like to upgrade what would the bet nvidia card be ? computer is a dual 4800+ with 4 gig memory and a 650 power supply everything but the mother board and case has been upgraded it has a 8400gs video card i want to play resident eveil 6 and a bunch of other games from steam that i have that are to new or too slow iv researched and it looks like a gtx550ti would be good i want to spend around 130 dollors less if possible would there be any performance upgrades or is there other options?