I am going for a new build after trying to fix up an older system. I have decided to go to haswell, probably an i5 rather than i7 for now. My main question is that I have (2) Asus GTX 760's now. I will be running (3) 2560 x 1440 displays (maybe more eventually?) Do I need to get rid of the 760's and go to 770's or 780's to keep up? Sending the 760's back and getting (2) 780's is another $500.