A:Answer I had a display port cable attached that only let me select 1920x1080 max resolution, but switching to hdmi I was able to get the full 2560x1080 resolution. You might try some of the software from LG https://www.lg.com/us/support/software-firmware-drivers?customerModelCode=34WL500-B&csSalesCode=34WL500-B.AUS (I assume the "on screen controller" software just allows things like brightness changes, the other is 'dual controller' for mac, which might provide additional software support for it.) But in the end, I'd be suspicious of the cable first and foremost, as I think natively any modern OS should be able to output 2560x1080 resolution.