A 35 USD CPU cooler with a 153 dollar Z170 motherboard that's paired with an i5-6500. I'm sorry, but that wouldn't be the smartest of moves if I'm fair.
Get the i5-6400, and pair it with this BLCK Non-K overclockable motherboard:
http://asrock.com/mb/Intel/Fatal1ty%20B150%20Gaming%20K4Hyper/
Also DDR4-2666 RAM or higher for 10+ fps boost in open world games by the way.