OS: Windows 8.1 Pro x64 (Custom Build)
Video Card: PNY Quadro K2200
Driver Version: 353.30
Video Ports Available: 2 x DP 1.2 and 1 DVI-I DL
Video out port of video card to monitor: DP1 of video card to MiniDP on monitor
Cable Used to attach the video card to the monitor: Cable Matters® Gold Plated Mini DisplayPort to DisplayPort Cable - 4K Resolution Ready
Windows Power Plan: Balanced
Resolution: 3840x2160 , 60Hz DP 1.2 Enabled
I have this in a dual monitor configuration with Dell U2412M. After a few minutes of working fine, my UP3214Q switches to the lower resolution.
Windows and Dell Display Manager reports the resolution as 3840x2160 while the monitor shows 1920x2160 @ 60Hz. Only the right portion of the 3840x2160 desktop is shown in the lower resolution.