I recently got my LG 34GN850 monitor. It's working just fine so far, but it is seemingly impossible to turn on HDR. My system supports HDR (GTX 980) and the monitor is supposed to have HDR support, but Windows just shows it as not HDR-compatible. There's no way to toggle it in the OSD (as hdr automatically turns on when a signal is received), but I can't enable it in windows either.

Checking in DxDiag, there are two lines that seem pretty contradictory. One called "Monitor Capabilities" lists the screen as HDR compatible, but right below, a line says Advanced Color is not supported. I haven't been able to turn HDR on in either games or Windows.

I'm not sure if this is some stupid setting I haven't found or if my monitor is defective, so any help would be really appreciated!

EDIT: Changing the cable fixed it. Not sure why but I swapped the old one out for an identical HDMI cable and it worked fine after that.