I am not an expert but i try to give few hints. Since it`s an older archetecture of the CPU there should be a problem with bottlenecking with a GTX 650 ti but I don`t know for sure and how much it would be. Maybe you could OC the CPU to the limits, if it the temperature is ok. Also I would not buy a nvidia card at this price segment and bottlenecking doesn`t harm the PC. A 7790HD is faster and cheaper than a gtx 650 ti, maybe you could go with a 7770HD but I can`t say for sure which card your gpu won`t bottleneck. Also you could use 2GB more RAM for gaming because it`s needed for new games and all programs and windows run faster with min 4GB RAM. Some Experts need to give the final advice for the graphic card.