I am thinking about buying a set of graphics cards to crossfire. My MoBo is a micro form with 2 PCI-e slots. I don't do any really serious gaming so I'm wondering if it would be better to use just 1 graphics card to help with heat? Or by having them crossfire, would they both run under less load and stay cooler compared to just 1 card? The cards would be very close together until I buy a new mobo.