I5-6600K with a decent overclock is arguably the best processor for gaming at any price.
80% will oc to 4.6.
The i7-6700K is similar, and costs more. But, so few games use more than 2-3 threads, the I7 hyperthreads will go largely unused.
ON the graphics card purchase, I might suggest A EVGA GTX970 if you are gaming at 1080P.
It will play anything well and is a tad stronger than the R9-380X.
The Plus is that EVGA has a 90 day trade up program that you might catch if Pascal launches within that window.