1. Why... Do you need 2 GTX 680s? Seriously, thats insane, even for an extreme gamer.
2. Have you considered GTX 670s in SLi? Honestly I consider 680s to be the one of the biggest failures in Nvidia history. The "released" the 680s, they were almost impossible to find for months because of the problems they had with their chip supplies, then they release the GTX 670, and its a hell of a lot cheaper and benches almost as good as the 680.
16gb 1600 ram $100
Z77 Board $150
hdd 1tb $100
PSU 1000watt $150
Add in the 2gtx680s and your at $1920. Add in windows tax and shipping and your at about $2,200 to $2,300.
If i had $1000 to blow on gpus i would rather have 2 gtx680. They are a little faster and the thermals/power are not so bad as to be unmanigable. Plus two cards gives you flex to run 6 monitors (non SLI) or to split them up if you need or wanted to part out the system.
I did a quick check, the 690's TDP is 300W (whereas 2x680 would be about 390). So it'd be quieter, cooler, and draw less power, but it would also be slightly less powerful (due to its lower clock rate), and not have the amount of display adapters that an SLI config would have. Right?
Oh, and yeah, it might be more difficult to sell than 2 680s.
Thanks I'll probably go with 2 670's but what are so bad about the 680's??? they perform better than almost any other card apart from the 690 and 6990.
Nvidia has always had problems moving to a new fabrication process, I guess the GTX 680 Kepler with full SMX enable makes it extremely difficult to manufacture. The 670's are defective 680's plain and simple they are crippled but still perform very close to the 680 in gaming, that is why the GTX 680 is a huge massive failure. AMD 7970 with 12.7 driver beat Nvidia at most things and are solid overclockers. If you need SLI buy 2 gtx 670's!