980ti is definitely not bang for the buck performance haha, but if you don't need the hyperthreading on the i7 and you'd rather have the best graphics performance possible then I'd go ahead with the 980ti
Also take note that the person above me suggested an 1150 platform with the i5 4690k. Can you explain why you're building a pc so we can better help you with what you are buying? For example if you just want to build it for gaming, then i'd go with the above(and get the 250gb samsung 850 evo). Skylake won't give you much better performance in games. The performance boost in games from sandy bridge to skylake is very negligible, hell you'd be fine on nehalem if all you'd be doing is playing games.
But as I said before, please state the use of your pc