Go into advanced mode for recording, and use your IGPU to record all your gameplay.
However, AMD GPUs really need headroom to insure that your video recordings don't become a sutterfest. So you'll want to limit your frame rate in games enough where you can have at least 10-15% GPU usage available for the encoder to use.
Then use a quality preset of CQP and something like 18, keyframes 2 and B frames 2.