Xrandr: can’t open display (trying to add fake display)
But after running the command xrandr it returns the Can’t open display error. I’ve tried display number 0 to 10 and only at xrandr —display :0 it returns: Authorization required, but no authorization protocol specified. Can’t open display :0
I’ve also tried to edit the .Xauthority file by running the following command: xauth add :0 . $(xxd -l 16 -p /dev/urandom) . But the xrandr command returned the Invalid MIT-MAGIC-COOKIE-1 key error
Afterwards I deleted the /etc/X11/xorg.conf file and the .Xauthority file . Then connected my monitor again and everything works fine again using my monitor. Also those files I deleted weren’t regenerated. How’s is it even possible to run Xorg without those files?
So does anyone have an idea how to properly fake this Xorg screen when no monitor is connected so that I can launch Sunshine and connect via Moonlight to my PC? If you need some more information; please ask!
EDIT: I’ve disabled gdm by running the command sudo systemctl stop gdm and started manually a Xorg process with the following command Xorg :0 -config xorg.conf -noreset .
So I can use the xrandr command now:
➜ ~ xrandr --display :0 Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767 HDMI-0 disconnected primary (normal left inverted right x axis y axis) DP-0 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 500mm x 281mm 1920x1080 60.00*+ DP-1 disconnected (normal left inverted right x axis y axis) HDMI-1 disconnected (normal left inverted right x axis y axis) DP-2 disconnected (normal left inverted right x axis y axis) DP-3 disconnected (normal left inverted right x axis y axis) I’m still not able to configure gdm correctly so it will start a Xorg process to display the screen to number 0 with the correct Xorg configuration
Thread: XRANDR «Can’t Open Display»
First Cup of Ubuntu 
Join Date May 2008 Location Castrimonno AltaMarca, EU Beans 4 —> Beans 4 Distro Ubuntu 9.10 Karmic Koala
XRANDR «Can’t Open Display»
Hi all, I’ve a very odd issue with my laptop and a VGA monitor.
The laptop is a HP Pavillion ZV5000EA (lubuntu 11.10) with ATI mobility radeon 9000IGP in it, but without it’s original lcd display because is broken so I torn it out and I’m using it with a VGA monitor.
I was used to use it with an LG Flatron L1910B and I was working awesomely.
Yesterday I changed the monitor with a Samsung SyncMaster 793s and it stopped working completely. I mean, just the video output, because the rest is still working. It has a ssh and vnc server in it and remotely I could see that the system was not crushed (and working). I checked xrandr in a console and it said «Can’t open display». I tried to reconfigure xserver, but it still cannot open the display. I also noticed that, booting, it doesn’t even show the bios splash screen nor the grub screen so I cannot choose the kernel to boot. Once booted the monitor shows a moving message with «Hz ??»
And now the ODD part. I plugged the laptop back to its beloved LG Flatron L1910B and it was working (as usual), than I unplugged it and plugged into the Samsung and it is working! WHY!? This is the output of xrandr:
Screen 0: minimum 320 x 200, current 1280 x 1024, maximum 4096 x 4096 VGA-0 connected 1280x1024+0+0 (normal left inverted right x axis y axis) 312mm x 234mm 1280x1024 60.0*+ 1024x768 85.0 + 75.1 70.1 60.0 1152x864 75.0 832x624 74.6 800x600 85.1 72.2 75.0 60.3 56.2 640x480 85.0 75.0 72.8 66.7 60.0 720x400 70.1 LVDS connected 1280x1024+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1600x1200 59.9 + 1400x1050 60.0 1280x1024 59.9* 1440x900 59.9 1280x960 59.9 1280x854 59.9 1280x800 59.8 1280x720 59.9 1152x768 59.8 1024x768 59.9 800x600 59.9 848x480 59.7 720x480 59.7 640x480 59.4 S-video disconnected (normal left inverted right x axis y axis)
Does anybody have experienced this behaviour, or have an idea? I really don’t know what to do, I googled like hell usuccessfully. Right now I’m using the LG monitor as a kick-start and I feel stupid.
5 Cups of Ubuntu 
Re: XRANDR «Can’t Open Display»
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.bak
If you come into same situation:
Try to find Horizontal and Vertical sync values for your monitor over google. Then edit xorg.conf. In most situations it is done this way:
Now edit the Monitor section and put right minimal and maximal values for Horizontal and Vertical sync.
The problem is that when you plug different monitor new values are put into xorg.conf. Sometimes monitors are detected ok sometimes are not.
First Cup of Ubuntu
Join Date May 2008 Location Castrimonno AltaMarca, EU Beans 4 —> Beans 4 Distro Ubuntu 9.10 Karmic Koala
Re: XRANDR «Can’t Open Display»
THANKS rmil!!
I didn’t have any xorg.conf to keep in safe and I made up a new one, blending the details of the graphic card and the monitor randomly found with google in this xorg.conf
Section "Device" Identifier "ATI Radeon" Driver "ati" Option "AccelMethod" "EXA" Option "MigrationHeuristic" "greedy" Option "AccelDFS" "true" Option "EnablePageFlip" "true" Option "EnableDepthMoves" "true" EndSection Section "Monitor" Identifier "Configured Monitor" Vendorname "Samsung" Modelname "Samsung SyncMaster 793S/793V/CM173G" Horizsync 30-71 Vertrefresh 50-160 modeline "640x480@60" 25.2 640 656 752 800 480 490 492 525 -vsync -hsync modeline "640x480@72" 31.5 640 664 704 832 480 489 491 520 -vsync -hsync modeline "640x480@75" 31.5 640 656 720 840 480 481 484 500 -vsync -hsync modeline "640x480@85" 36.0 640 696 752 832 480 481 484 509 -vsync -hsync modeline "800x600@56" 36.0 800 824 896 1024 600 601 603 625 +hsync +vsync modeline "800x600@72" 50.0 800 856 976 1040 600 637 643 666 +hsync +vsync modeline "800x600@75" 49.5 800 816 896 1056 600 601 604 625 +hsync +vsync modeline "800x600@85" 56.3 800 832 896 1048 600 601 604 631 +hsync +vsync modeline "800x600@60" 40.0 800 840 968 1056 600 601 605 628 +hsync +vsync modeline "832x624@75" 57.284 832 864 928 1152 624 625 628 667 -vsync -hsync modeline "1024x768@85" 94.5 1024 1072 1168 1376 768 769 772 808 +hsync +vsync modeline "1024x768@75" 78.8 1024 1040 1136 1312 768 769 772 800 +hsync +vsync modeline "1024x768@70" 75.0 1024 1048 1184 1328 768 771 777 806 -vsync -hsync modeline "1024x768@60" 65.0 1024 1048 1184 1344 768 771 777 806 -vsync -hsync modeline "1024x768@43" 44.9 1024 1032 1208 1264 768 768 776 817 +hsync interlace +vsync modeline "1152x864@75" 108.0 1152 1216 1344 1600 864 865 868 900 +hsync +vsync modeline "1280x960@60" 102.1 1280 1360 1496 1712 960 961 964 994 -hsync +vsync modeline "1280x1024@60" 108.0 1280 1328 1440 1688 1024 1025 1028 1066 +hsync +vsync modeline "1400x1050@60" 122.61 1400 1488 1640 1880 1050 1051 1054 1087 -hsync +vsync Gamma 1.0 EndSection Section "Screen" Identifier "Default Screen" Monitor "Configured Monitor" Device "ATI Radeon" Defaultdepth 24 SubSection "Display" Depth 24 Modes "1024x768@70" "1024x768@60" "1024x768@75" "1024x768@43" "1024x768@85" "1152x864@75" "832x624@75" "1280x960@60" "800x600@60" "1280x1024@60" "800x600@85" "1400x1050@60" "800x600@75" "800x600@72" "800x600@56" "640x480@85" "640x480@75" "640x480@72" "640x480@60" EndSubSection EndSection
Now it works as it should! Thanks agaig, I thought that with xrandr there was no xorg.conf to set