display port monitor not useable after standby/poweroff and power on again


Have this problem on two computers, one with openSuSE (previously 13.1, now tumbleweed) having a GTX970, the other running Mageia 5 having a GTX980Ti.
Connected Display is a Samsung U28D590, running with 3840x2160@60Hz connected via DisplayPort. Same display for both machines (no switch or anything in between, direct connection).
System runs normally fine, but when I turn off the display for a while and then turn it on again, the screen remains black. (Has to be off a bit longer, like a minute or more, not reproducible with only a few seconds off-time). The only way I’ve found so far to reactivate the display is to restart the X-Server so the gpu gets re-initialized. This only happens with high resolution modes. The standard text-console (tty) remains usable.
Driver used is latest version: 361.28. But also happened with all others before that support the GTX900 series.
Having to keep the display powered up fully all the time while letting the computer run a lengthy job that requires the X-Server is not a good workaround.
This was no problem before when I still had a GTX580 with a display connected via DVI. So the X-Server shouldn’t be the problem.

I have the same issue on a GTX 950 on 4k@60hz. There seems to be some sort of bug in the driver. I ended up writing a script to fix this for my mythtv box till this gets resolved. I think it might have something to do with the HDCP but there’s no confirmation either way.

Similar thread here with no resolution


Here’s my thread at ubuntu forums


one guy said it was xfce-settings needing to be downgraded but no confirmation of that either since most people that are posting here at nvidia forums aren’t mentioning what distro / window manager they are using.

anyone have more details?

thanks for the links.
But I don’t think xfce-settings is the main issue as on the openSuSE machine I’m using KDE. With the Mageia-PC it actually is XFCE, but have to look where to find older packages as the repositories only offer 4.12… will see if I find something…
But it can’t be a long-term solution to have to stick to old packages (if it works). Should be fixed at the root of the problem. Because the problem also exists - if somewhat different - on ms windows, but there it’s like the desktop is coming up again but is “re-sorted” as if it temporarily had a resolution of 640x480. So it is something that is at the very core of the driver or somewhere hardware bug (which should also be fixable through drivers).
Regarding the script: as I’m using a normal desktop PC, how do I bind it efficiently? In my case I don’t have a specific power on signal from a remote and don’t want it to run constantly or having to switch to a terminal and login there to run the script to reactivate the display. I mean, is there any signal / event that notifies about the display being switched on again (that nvidia fails to react upon but at least passes through)?

There’s a QT bug that causes this in KDE: https://bugreports.qt.io/browse/QTBUG-42985 .