Ok I want to upgrade my motherboard and graphics cards. What do you think is better buy 2 " ASUS ARES/2DIS/4GD5 RADEON HD 5870 X2 4GB " and download the " IZ3D - ATI 3D DLP Enabled Driver " (which I have to pay a bit more) or 2 " ASUS Radeon HD 6870 EAH6870/2DI2S/1GD5 "?