Changing screen resolution using xorg.conf file

Question

I recently (today) installed Nvidia graphic drivers on my laptop, I followed the instruction on the tutorial and generated a xorg.conf file using nvidia-xconfig. I have am using a laptop and have plugged an external montior to it, The external monitor's resolution is fine however the main laptop screen has gone to 4:3 resolution. I have no idea what's in the xorg.conf file, I have never seen anything like this, can anyone help me changing the screen resolution back to 16:9, 1366x768.

Here is the xorg.conf file.

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 390.48  (buildmeister@swio-display-x86-rhel47-07)  Thu Mar 22 01:07:32 PDT 2018


Section "ServerLayout"
    Identifier     "layout"
    Screen      0  "nvidia" 0 0
    Inactive       "intel"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Keyboard0"
    Driver         "keyboard"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       60.0 - 100.0
    VertRefresh     60.0 - 100.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "nvidia"
    Driver         "nvidia"
    BusID          "PCI:1:0:0"
EndSection

Section "Device"
    Identifier     "intel"
    Driver         "modesetting"
EndSection

Section "Screen"
    Identifier     "nvidia"
    Device         "nvidia"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "AllowEmptyInitialConfiguration"
    Option         "RegistryDwords" "PrefLevelSrc=0x2222"
    Option         "TripleBuffer" "True"
    SubSection     "Display"
        Depth       24
        Modes      "nvidia-auto-select"
    EndSubSection
EndSection

Section "Screen"
    Identifier     "intel"
    Device         "intel"
    Monitor        "Monitor0"
EndSection

Solution

Okay so after scrounging the web, this is the solution I came up with. I was using the manually generated xorg.conf file by using nvidia-xconfig. Which wasn't generating the correct config. This is what finally worked for me.

Press ctrl+alt+f2 (or whatever key combination you use to get into command line mode)

Login as the administrator.

If you're using GDM like me go ahead and stop the process, using service gdm stop.

Check if your X-server is running or not. Use ps -C Xorg and then kill the process. kill -9 PID

Use Xorg -configure which will generate xorg.conf.new

now simply move the .new file to the /etc/X11/ directory, using
mv xorg.conf.new /etc/X11/xorg.conf

now restart the GDM service gdm start

And you're done.

Comments

[nobody]

What is external monitor resolution? Is it 4:3? Do you have desktop mirrored to have the same picture on both screens? If you have mirrored picture than the resolution will be the same on both.