i have a prebuilt set up running a H87M-E (ASUS MOBO) ,i3 intel chipset with a GEFORCE GTX 650 gpu, its running on a Coolmaster GX2 550Ws power supply, i was thinking of swapping out my GPU to a better one so i can get back to playing BF4? Any recommendation for a new GPU (looking towards mid range price wise) also should i change my power supply?