If I were to be you, I'd wait a bit. Nvidia's new cards, expected to come out in April 2016 (like 2 months form now) will cost the same, and give 5-10x the amount of performance. It looks really promising. You should really wait because it would just be a waste of money to buy a Titan X now, while you can get a similar card for half the price in 2 months.
That new GPU series is called "Pascal", so that's what Garry is talking about.