Hello, I am considering a new build (gaming) with a X79 mobo (Asus Rampage IV Black Edition) and Evga 780TI Classified cards. For now one card but I plan on adding a second soon and maybe a third later. I am using a BenQ 27" 120hz monitor (want the option to add two more later). My question is this: Since the 780TI cards are only available in 3GB, will that be enough to run 3 120hz monitors with 3-way SLI? I would hate to have to pay more for a lesser card like the Titan just because it has 6GB. Thank you!