If you've been waiting for a card that will be able to push game content to all three of your new 4K displays, the wait may soon be over. It appears that some benchmarks and specifications for the upcoming generation of video cards based on NVIDIA's latest chip have leaked. Both of these cards look to be pretty impressive and I'm thinking that the 970 may be in my future. As always, take these "leaks" with a grain of salt. Many things could change before release.
...GTX 970 is looking sharp with plenty more OC headroom . That's only 1140mhz. According to TPU GPU DB of a bunch of different cards, 1178mhz should be the reference boost clock for the GTX 970. An 1150mhz GTX 780 Ti which is a healthy air OC for one, scores around 12,200 gpu score. That sub-reference-clock GTX 970, pumps out an 11,300 score which is under 10% less. Now realize that you can buy a 1280mhz or higher out of the box card at launch.
Source: HardOCP Forums