I would use PCpartspicker.com It's what I used for my build. In my opinion, I recommend the Skylake intel i5 (6th generation). I built mine for about $800 so here are my specs:
Motherboard: Gigabyte Gaming 3 Z170X
CPU: Intel Core i5 6500
GPU: EVGA GTX 950 SSC
RAM: EVGA DDR4 RAM @2133mhz
SSD: Samsung EVO 850 (250gb for Windows)
HDD: WD 2TB Black Edition
PSU: Cooler Master 550w Power Supply
CPU Cooler: Cooler Master Hyper TX3
Windows 10
It runs pretty much everything I throw at it. But the CPU cooler is definitely are requirement in this build as the intel stock cooler sucks. Hope this helps!