I recently got a new GPU (NVidia GTX 750) works like a charm, i can run games ranging from TF2 to Borderlands 2 at max settings at 70 fps average. But when i enter a multiplayer server or engage in combat, the fps drops to around 30 fps. I think it's because there is a lot of enemies on the map so it lags. I currently have the AM FX(tm)-4100 Quad-Core Processor (4 CPU's) ~3.6GHz.