I've spun my wheels trying to tweak this and I need some help please. Win10, Nvidia GeForce 1080ti, 4K/HDR HDMI and Predator XB321HK. I can't seem to get my refresh rate above 30hz in 3840 x 2160, or I don't have the option to in any settings through Win10. Nvidia graphics settings is what I've been going through and it shows my native resolution is 1920 x 1080. Says everything should be capable/compatible. I've replaced my HDMI cable thinking I just bought a bad one and didn't see any change. So I'm guessing I'm just overlooking a setting. Anyways, I appreciate any input. Have a great day!