What are you planning on doing with the PC?
AMD is absolutely NOT worth it right now, even their latest CPUs are weak. Their 8 cores don't even come close to the power of Intel 4 cores.
If you're looking for gaming and perhaps some video editing and/or streaming, go with i7 6700k or i5 6600k; 4 and 6 cores respectively, though the latter is rather expensive still. I do all of the aforementioned work on my PC, and I have an i7 6700k with 16GB of DDR4 3000 RAM, and it works perfectly.