So I have an XPS 17, windows 7 with a quad core i7, 12gb of ram, a 3gb nvidia gt 445m card, and a 7200rpm hard drive. Even with low settings games lag a huge amount, I'm mainly playing Civ 5 and Borderlands 2. I updated the drivers of my graphics card, defragged my disc, and my computer doesn't run that hot. What else can I do? Thanks