Ubuntu 16.04 resolution stuck at 4k

Question

First of all i am a total linux noob. I just installed Ubuntu 16.04 on a computer that is connected to a tv with hdmi. But i can't change resolution from 4k, i want to use 1080p instead. My computer has a i5 7400 and i am using the build in intel graphics. I have installed the intel drivers using the Intel Graphics update tool v2.0.2.

I have read in other threads that i can add a resolution with xrandr --newmode but i get an error.

i get the following results:

xrandr

xrandr: Failed to get size of gamma for output default Screen 0: minimum 3840 x 2160, current 3840 x 2160, maximum 3840 x 2160 default connected primary 3840x2160+0+0 0mm x 0mm 3840x2160 88.00*

cvt 1920 1080 60

1920x1080 59.96 Hz (CVT 2.07M9) hsync: 67.16 kHz; pclk: 173.00 MHz Modeline "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync

xrandr --newmode "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync

xrandr: Failed to get size of gamma for output default

Can anyone help me with what to do?

Answer 1

You can reconfigure xOrg. I did this by creating a file in my /usr/share/X11/xorg.conf.d Directory.

I made it using vim:

sudo vim /usr/share/X11/xorg.conf.d/5-monitor.conf

Here is an example of my file. (mine was configured for 4k but I edited it to 1080p so you'd get an idea of what it would look like) if you follow the tutorial below it should help you build your own xorg config file.

Section "Monitor"
   Identifier "Monitor0"
   Modeline "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
EndSection
Section "Device"
   Identifier "Device0"
   Driver "intel"
EndSection
Section "Screen"
   Identifier "Screen0"
   Device "Device0"
   Monitor "Monitor0"
   DefaultDepth 24
   SubSection "Display"
      Depth 24
      Modes "1920x1080"
   EndSubSection
EndSection

For directions on how to do this you can follow this tutorial: https://wiki.gentoo.org/wiki/Xorg/Multiple_monitors