I'm planning to buy a Asus R9 270X Direct Cu2 TOP with intel core i5 3450. Just wanted to know if my rig will be bottlenecked or not?? My PSU is 500w (can upgrade to 550W if needed) , single 1080p monitor and I mainly need it for gaming.. Btw if my rig is balanced, will the gtx 660 be better or the 270x.. Thnx