having read all the 6 pages look like it could be very well that the apu is capable of decoding high bitrate hdr content but just that technology (tv, motherboard..) is not ready to transfer HDR 4K @ 60fps.
because basically if the player decode your hdr 4K 60fps content and tv is showing it doesn't mean you'r tv actually received the content in hdr / without subsampling.
since most movies are still in 30fps ish anyway, what I actually wonder is if there any setup (one of you'rs) where it's possible to 4:4:4 HDR (10bits) 4K @ 24fps.
It's what basically most UHD movies are, either really HDR or just 10/12bits colors, would be somehow some same kind of bitrate needed.
but for now with the specs you are seeing in the settings it look like chroma subsampling is ALWAYS active for 4K 10bits content.
that what make me wonder if it doesn't worth waiting new versions of hdmi become more standards, and so maybe new motherboards.
just to remind everyone that a 100$ android box can do the same as your complete pc build with ryzen. i.e. play HDR 10bits 4K thanks to their HDMI 2.0a output.
look like 0 mini itx board (even atx) do HDMI 2.0a/b, the one asus strix mentioned is tricky, say HDMI 2.0b ready but still say output is hdmi 2.0. This is not clear and come at a premium that can buy almost 3 4KHDR HDMI 2.0a android tv box.
of course it will be a real pc and that's nice. just saying that 600$ config with amd last apu etc seems to struggle for correct 4KHDR output while android box at 100$ do it just fine.
