Tag Archives: xrandr

Ubuntu Resolution Change xrandr Failed to get size of gamma for output default

1.Questions

Version information description: Ubuntu 16.04 lts

After installing Ubuntu, resolution and display do not match . The xrandr command cannot give relevant information. So we tried different methods.

2.Xrandr — addnewmode

This is the most frequently answered method on stackoverflow

gtf 1920 1080 60

1920×1080 resolution, 60Hz refresh rate

So you get a modeline:

"1920x1080_60.00"  172.80  1920 2040 2248 2576  1080 1081 1084 1118  -HSync +Vsync

Copy this line and run it

xrandr --newmode "1920x1080_60.00" 172.80 1920 2040 2248 2576 1080 1081 1084 1118 -HSync +Vsync

Add one more:

xrandr --addmode VGA1 "1920x1080_60.00"

Here, vga1 can be HDM and others (have no idea about this)

Finally:

xrandr --output VGA1 --mode "1920x1080_60.00"

But their own is to run xrandr can not give a response, there are errors. So it doesn’t work.

3.xorg.conf

1 sudo vim /etc/xorg.conf

Copy the following:

Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Monitor Vendor"
        ModelName    "Monitor Model"
        HorizSync   28.0 - 70.0
        VertRefresh     56.0 - 75.0
EndSection


Section "Device"
        Identifier  "VMware SVGA"
        Driver      "vesa"
EndSection


Section "Screen"
        Identifier "Screen0"
        Device     "Card0"
        Monitor    "Monitor0"
        SubSection "Display"
                Viewport   0 0
                Depth     24
                Modes     "1920x1080_60.00"
        EndSubSection
EndSection

: WQ! (save)

Restart and it’s successful.

4.Postscript

You also see a way to change the grub startup file. But it didn’t work for me.