Personally i'm using a two PC setup now. One i use to play on, the other to record. My recording PC has an elgato HD pro 60 installed, which just captures the entire screen of my gaming PC.
Before that i used OBS to record. It'ss free, easy to setup, has lots of options and pretty good CPU performance wise. Can't recommend it enough!
Small tip, no matter what you end up with, always make sure to record game audio and your microphone on two separate channels so that you can adjust volume and cut out game or commentary without affecting the other.
OBS has some built-in options for that as well!
-SC