I recently posted about having two Nvidia GT640 cards in my desktop, it came with one and I purchased another to run physx. The performance is okay but I am wondering if it is better to have two graphics cards or one powerful one. I am getting into pc gaming and want the most bang for the buck. I am still within the return and exchange policy of the one I purchsed. About my PC: i7 4770 3.4, 16GB ram, 2TB @7200, 2 AOC 23" ips displays and one 51" Samsung tv.