[ubuntu] Screen resolution downgrades after unlocking/waking monitor

I was having this same issue ruing 14.04 (64 bit) and have now done a fresh installation of 16.04 (64 bit) to find the problem persists.

I have a Dell 27" 4K monitor attached to a Lenovo W530 via a display port cable (no docking station). I set the monitor to 3840 x 2160 (16:9). The computer is set not to go do sleep. The display was going to sleep and locking. (If the screen never sleeps/locks, this does not happen.) I am ruing the latest supplied Nvidia driver currently.

When the monitor sleeps/locks and I retu to it, initially the display is still set to 4K but after some short span of time (a minute? less?) it downgrades the resolution to 1920 x 1280.

You have no idea how aoying this is. There must be a way to make it persist. I just can't seem to guess at it.

Here is the thread from my 14.04 inquiry over the same matter:

http://ubuntuforums.org/showthread.php?t=2310370

Any insight would be greatly appreciated.