What does the graphics card do where HDR is concerned? I thought it was monitor based?
The GPU still needs to be able to process the HDR content. The grunt that a current GPU may be enough but it depends on the software for processing.
Basically at the moment we transmit in 8-bit which offers 16.7 million shades, HDR-10 offers 1 billion shades and Dolby Vision 68 billion shades. The source content needs to be HDR and then the TV processes from the source.
Of course with gaming the PC is the source so the GPU has to render the game in HDR to send to the TV/Monitor. That is my understanding to it.