LATEST UPDATE: I feel like somewhat an idiot; I have been able to resolve this issue mainly by turning off the monitor completely - usually I have it on and it auto-sleeps after a period of inactivity or no input to the display. If I leave the monitor on and then turn on my pc, I get this issue. If I turn it off for a minute or more, then turn it on sometimes even after I have turned the computer on, it will more reliably detect and use the 4k 60Hz resolution. Still never had *any* issues with my previous cards that are 4-5 years old with leaving the monitor on, and it my research it seems other folks get these types of issues so it would be great if someone would troubleshoot and fix, seems to be a driver issue but that is mostly speculation.
Only very intermittently am I able to get displayport 1.2 4k @ 60hz. ** usually maxes at 30hz, or sometimes bumps me down in allowed resolution (as checked in display adapter properties.)
I have tried all ports using various cables confirmed working at that resolution with older card... this is a newer card, designed for higher resolution, with supposedly displayport 1.3/1.4 ports... so why am I not able to drive my 4k monitor at 60hz, I am using short cables... not long ones and again they have been tested functional with other setups... so looks like something is wonky. PLEASE HELP, this really is a killer issue to deal with, I may just sell the card because it is so unreliable.
STILL BROKEN **UPDATE: replacement card experiencing same issue although not even able to sometimes connect now so I guess it's even worse than before...
Ought to be a "3840 by 2160, True Color (32 bit), 60 Hertz" Option.