Connecting LG27UL850 to MacBook Pro 13" 2015 at 3840x2160 60hz I have just bought the LG27UL850 and plugged the LG supplied hdmi cable in to my MacBook Pro 13" 2015. I can only get 3840 x 2160 (low resolution) at 30hz. I want this resolution at 60hz which I know is possible but I'm not sure how. Does anyone know which adapter will help me do this? Thunderbolt 2 to HDMI? Display port to mini display port? Am i the only one that finds this mega confusing?!
A 4k resolution at 60 Hz over HDMI requires HDMI 2.0, which your MacBook Pro does not support.

Instead you'll need to use the Thunderbolt 2 port with a mini-DisplayPort to DisplayPort cable, which supports 3840x2160 at 60 Hz.