I found this tool to set hdmi black level to limited (16-235) or Full RGB (0-255) with one click of a button make sure you restart your computer and also make sure ur PC monitor supports Full RGB if not you will get Crushed Blacks. you will notice your colors will get richer and blacks gets inky if your monitor supports it.
I am using Sammy 27 inch and for those Samsung newer model users set your HDMI Black level to normal from low after toggling to Full RGB.