NUC5i7RYH won't work in 4K at 60Hz with Asus PQ321Q monitor in MST mode

Just got the NUC5i7RYH installed with a fresh copy of Windows 8.1 Pro. 

I have the computer attached to an Asus PQ321Q 4K monitor that is set in MST mode using a high quality Displayport cable.  When in this mode, the display only shows on the left side of the monitor.  If I set the monitor to SST mode, I get the full screen but it only works at 30Hz.  I would like to get the monitor to be used in 4K at 60Hz.  The same monitor in MST mode with the same cable works great with my Apple 2013 Mac Pro. 

I did update the NUC5i7RYH with the latest Bios and the latest beta display drivers from Intel's download page. 

Any help to get this configuration working correctly would be great. 

Thanks!