I am trying to get HDR video playback from my PC using an RX 480. I do not like Windows 10 CU's 'Film ^& TV' application and instead prefer using MPC-HC + MadVR. Unfortunately it does not work well with AMD's drivers. Unlike the Nvidia drivers the AMD drivers do not contain a private API that allows 'on-the-fly' switching between SDR and HDR modes. The AMD solution relies entirely on Windows and is clunky as heck. For more details see this post by Madshi, the creator of MadVR.