UP3214Q/UP2414Q - 1/2 screen issue and/or No picture after powering off, then on

I woke up this morning and my rev A01 up3214Q wouldn't wake up on my mac pro 2013.  I then double tap the menu and half of the screen showed up.  I then turned it off for like 10 seconds and turned it back on, which fixed the issue.  

I'm a little concerned how bad this problem is.

I gave up trying to sort issues out with Dell. They seem to be a company that is not able to handle modern market. After weeks of trying I've finally set up a service call with them, but whole deal failed two times in two weeks. 

First it seems that Dell does not recognize all the money the same way. Two thousand+ euros from me in Croatia is not the same as from someone living in France, no matter we're all in EU. They insist that I ship my old monitor to some of their service centers, spend hundred+ euros on postal services, stay without monitor for indefinite time awaiting replacement. In the same time they allegedly send engineers to premises for some services in some countries. 

Really funny. In 2014. when UPS/DHL/FedEx etc. send cars from USA to EU in four days, when I ship computer parts on daily basis within 2 days inside EU, Dell can't ship a replacement to a customer of a 2,5k euro display. What if I made a mistake and suggested my colleagues to buy those... 

Really Dell??

Anyway, will probably just return it for full refund and buy from other manufacturer, since to buy a display this expensive and have it unserviceable is totally unacceptable with such treatment and RMA process from ancient times, more fitting a startup from Africa, than Dell. (no offense to startups from Africa)

Something to consider I recently did some windows updates and the monitor seems to be more stable, for some weird reason, previous to the windows update, when I do a login into my computer I will get a very small centered window login frame, now with the windows update I get a full monitor login. p

Owners of the Revision A0 monitor are informed by Dell that there is no software more recent than that available for download on the Dell website on the monitor's page.

Problems of this sort may be at the desktop, according to Dell technical support. For those using Intel integrated graphics, a firmware update which specifically addressed 4k monitor issues was released around April 2014. Try the latest intel drivers and try also updating the motherboard firmware.

Users of nvidia graphics cards might also be running into problems discussed on the internet, where the graphics card, after a certain number of attempts at sending a signal to display port, gives up, and thereafter tries only via hdmi. Users might find success by resetting this nvidia count. One method would be to remove power from the PC as well as the motherboard battery for a while. (The BIOS will need to be reset afterwards,. probably). The card may then start sending signals to the monitor again. Maybe (!) there is a simpler way to reset the nvidia count, if this actually is the problem.

Yeehi, can you provide references to this nvidia count method? I cannot find anything about it when I try searching. This is the first I've heard about it.

humba, I could never get 2560x1440 to work at 60 hz either.

However, in another forum I read this:

The monitor will happily accept 2560x1440 in DP 1.1 mode and do 60Hz, I am surprised the nvidia drivers are being weird but that is windows for you... In linux no problem doing 2560x1440 at 60Hz in both SST or MST modes (in MST mode giving it 2x 1280x1440 halves).

So this may be an EDID or NVIDIA windows driver issue. Myself, I couldn't get it to work even with defining a custom resolution in the NVIDIA control panel nor could I get it to work with ToastyX's CRU (Custom Resolution Utilty). :(

I'm a mac user.  Luckily I can use 2560x1440 60hz on scaling mode which looks great.  It kind of defeats the purpose to scale down a 4k display like that.  Hopefully, this will be added to windows too.

I've got a rev. A00 and a lot of what I have been experiencing (mostly) are post issues.  However when I boot into Windows with the monitor off I turn back on the monitor and works as expected.

I have done some tests today and seems there is more solutions:

When I turn off CSM in the motherboard BIOS options, it shows picture during POST time on DP 1.2

When I connect both DP and HDMI cable from the monitor to the Nvidia GPU and use DP 1.2 it also seems to show picture on every POST.

Edit: I was wrong about HDMI. It seemed to work first but I realized that it does not.
But setting CSM to off still seems to work.

I sold my Nvidia 660Ti and bought AMD 280, have no issues with cold boot or restart. I experience issues with wake from sleep only, but even that is occasionally.

ASUS Z87 Gryphon, ASUS R9280-DC2T-3GD5.

So this seems to be a NVIDIA issue?

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