3rd one, but the newer 2600X would be a better choice if you can get it - just bear in mind older motherboards would need a BIOS update.
If you wanted to go intel go and can't afford to go with an 8600K + 1070 then get an 8400 + 1070. Forget the 7700, while it is a good gamer buying a 4 core CPU now that there are all these 6 and 8 core options feels like the wrong choice to me. The 8400 is just better.
Edit: also you can use a cheaper motherboard with the non-k intel CPUs which gives you more money for the GPU.
My thoughts basically summarise to:- any 6 or 8 core ryzen or i5/i7, 16GB of RAM, any reasonable motherboard that is compatible, and the best graphics card you can afford