I have a new Dell U3219q, and am trying to get it to run 4K@60 on Windows, but it only allows me to choose between 29 and 30 Hz. My computer is a Lenovo T450 with HD 4400 graphics. I have tried creating a new custom resolution, but it fails with "custom resolution exceeds the bandwidth capacity." It is currently set with the default 128M of dedicated video memory - do I need to increase this in BIOS?
