Nonscrub :
So what is the best i7 in terms of clock rate and performance. I also mean for gaming too.
Well, if you go just by best clock rate and single core performance, then that is the Core i7 6700K.
However, the best all around Core i7 would be one of the Haswell-e processors, the Core i7 5930K or 5960X. I personally like the 5930K because of it's higher clock rate than the 5960X and added cores over the 6700K, making it very good for gaming, steaming, rendering, just about anything one would want to use their computer for. But I do believe in June Intel will be offering new Haswell-e 8, 10 and 12 core processors to replace the 5820K (6 core), 5930K (6 core) and 5960X (8 core).
So, if all you plan to do that taxes your processor is gaming, the Core i7 6700K is the best. But if you want great gaming and to be able to do everything else that would really tax your computer, then a Haswell-e processor would be the better choice. Since the i7 6700K uses a Z170 motherboard and the Haswell-e i7s use the X99 motherboards, one should give some thought to what they expect to be doing with their computer. No right or wrong answer... just choices for what one plans to do.