Hello guys , currently I have to make a decision here, I m using an Asus direct cu II 670 2 gb card now , but a friend of mine is wanting to swap me with his 4 gb Asus direct cu II 680, because he wants to go sli 670 , I only game on 60 hz 1920x 1080 monitor , no triple monitor or sli for me unless I win the lottery , cpu 2700k, so am I better off swapping or keeping the 670? Cuz I know 680 is slightly faster than 670..but I heard the extra memory will have more latency..so please help