I recently bought an RX 6800 XT and paired it with an LG OLED48CX 4K 120 Hz TV. I am very happy with my setup but I am wondering if anyone can confirm if 10 bit + 4:4:4 is working? I can only get parts of it to work if I run 60 Hz, then I can choose 4:4:4 and the 10 + 12 bit option show up. But choosing 10 bit resets the setting to 8 bit. And I don't know if it's due to my HDMI cabel, if GPU doesn't support it or if the TV doesn't.
The nVidia 3000 series had similar issues when they first launched back in September but since LG updated the firmware with a fix and got it working on their CX series of TV's (and last years C9's I believe).