The 970 preforms less than 1% worse than the 780ti, and the 970 is cheaper, less power consuming and runs cooler
Based on your previous posts, here is a build that should suit you needs. Water cooled, a 1440p monitor and an OS. It also contains a Z97 motherboard, which is Intel's latest chipset, allowing for future upgrades and further expansion later on.
http://pcpartpicker.com/p/RDm4P6
I really would have liked to put in an additional SSD, but couldn't fit it into the budget with the 27" monitor.
Here is one with a 24" monitor ($200 cheaper) but for the GPU you are getting, a 27" 1440p monitor would look fantastic.
http://pcpartpicker.com/p/6sj3WZ