<html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> </head> <body text="#000000" bgcolor="#FFFFFF"> Overview: <blockquote> I am having an issue with my Dell P2715Q monitor not waking up from standby, suspend, and off. This problem seems to only occur on Linux. I have tried Windows 10 and the Dell monitor seems to wake up o.k. so far. The monitor is connected through a display port. I would appreciate help solving this problem. I have created a script using the output from "xscreensaver-command -watch" to use xrandr to turn the screen on, but this is a bit of a band-aide since the screen becomes visible behind the screen saver while the Dell monitor is being turned back on by the script. </blockquote> Details of the problem: <blockquote> I am using xscreensaver and have found that after I locked the screen and come back only my one monitor wakes up It was suggested that I try to replicate the issue using xset. so I used the command: sleep 1; xset dpms force off <blockquote> I tried off, standby, and suspend with xset and they all showed the same issue. The Dell monitor does not wake up. If I type "sleep 1; xset dpms force off", only my Samsung monitor wakes up. The Dell monitor briefly shows a box saying "Entering energy saver mode" and then does not wake up. If I type " xrandr --output DP-2 --left-of DVI-D-0 --auto" it does turn the monitor back on. Also, I am including the output from xrandr -q below to show the two different states for the monitor: after it has failed to wake and when it is operating normally. </blockquote> </blockquote> What I have tried: <blockquote> The command xrandr --output DP-2 --left-of DVI-D-0 --auto will bring the monitor back online. </blockquote> <blockquote>Hardware related: <blockquote>Different DP<->DP cable DP<->mDP cable (cable that has mDP on the monitor side and standard DP port on the graphics card side) Connecting monitor to HDMI. When connected to the HDMI port it wakes fine, however HDMI only supports 30 Hz at the 3840x2160 resolution. Contacted Dell but that were not interested in helping with the issue since it involved Linux. They say they do not support Linux. However, I wonder if this is really an Energy Star compliance issue. In any event since it works on windows it should be possible to make it work correctly on Linux. </blockquote> Software related: <blockquote>I have tried upgrading to the latest available kernel (4.10.0-27-generic) and have tried older versions but the kernel version did not resolve the problem. I have tried different versions of the NVIDIA driver but these also did not effect the problem. Currently running nvidia-384 (version 384.59-0ubuntu0~gpu16.04.01). </blockquote> Windows 10: <blockquote>Monitor sleeps and wakes up normally. </blockquote> I have tried the Cinnamon window manager in addition to XFCE and have tried different screen savers. I have verified the problem directly using xset as mentioned above </blockquote> Hardware: <blockquote> I have 2 monitors connected <ol> <li>Dell P2715Q connected to display port</li> <li>Samsung monitor connected to DVI port</li> </ol> Graphcis card: Asus GeForce GTX 1060 Kernel:4.10.0-27-generic X.Org X Server version: 1.18.4 Running Linux Mint Window manager XFCE4. I have also tried Cinnamon. Motherboard: Asus Maximus VIII Hero </blockquote> -------------------------------------------------------------------------------------------------------------------------------------------------------------- xrandr -q when the Dell monitor did not wake from sleep: Screen 0: minimum 8 x 8, current 1680 x 1050, maximum 32767 x 32767 DVI-D-0 connected 1680x1050+0+0 (normal left inverted right x axis y axis) 474mm x 296mm 1680x1050 59.88*+ 59.95 1280x1024 75.02 60.02 1280x960 60.00 1152x864 75.00 1024x768 75.03 70.07 60.00 800x600 75.00 72.19 60.32 56.25 640x480 75.00 72.81 59.94 HDMI-0 disconnected (normal left inverted right x axis y axis) HDMI-1 disconnected (normal left inverted right x axis y axis) DP-0 disconnected (normal left inverted right x axis y axis) DP-1 disconnected (normal left inverted right x axis y axis) DP-2 connected primary (normal left inverted right x axis y axis) 3840x2160 60.00 + 2560x1440 59.95 1920x1200 59.88 1920x1080 60.00 60.00 59.94 50.00 23.97 60.00 50.04 1680x1050 59.95 1600x1200 60.00 1280x1024 75.02 60.02 1280x800 59.81 1280x720 60.00 59.94 50.00 1152x864 75.00 1024x768 75.03 60.00 800x600 75.00 60.32 720x576 50.00 720x480 59.94 640x480 75.00 59.94 59.93 DP-3 disconnected (normal left inverted right x axis y axis) -------------------------------------------------------------------------------------------------------------------------------------------------------------- xrandr -q when both monitors are operating normally <blockquote> Screen 0: minimum 8 x 8, current 5520 x 2160, maximum 32767 x 32767 DVI-D-0 connected 1680x1050+3840+0 (normal left inverted right x axis y axis) 474mm x 296mm 1680x1050 59.88*+ 59.95 1280x1024 75.02 60.02 1280x960 60.00 1152x864 75.00 1024x768 75.03 70.07 60.00 800x600 75.00 72.19 60.32 56.25 640x480 75.00 72.81 59.94 HDMI-0 disconnected (normal left inverted right x axis y axis) HDMI-1 disconnected (normal left inverted right x axis y axis) DP-0 disconnected (normal left inverted right x axis y axis) DP-1 disconnected (normal left inverted right x axis y axis) DP-2 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 597mm x 336mm 3840x2160 60.00*+ 2560x1440 59.95 1920x1200 59.88 1920x1080 60.00 60.00 59.94 50.00 23.97 60.00 50.04 1680x1050 59.95 1600x1200 60.00 1280x1024 75.02 60.02 1280x800 59.81 1280x720 60.00 59.94 50.00 1152x864 75.00 1024x768 75.03 60.00 800x600 75.00 60.32 720x576 50.00 720x480 59.94 640x480 75.00 59.94 59.93 DP-3 disconnected (normal left inverted right x axis y axis) </blockquote> <blockquote> </blockquote> </body> </html>