How to extend display to the secondary monitor without logout at Gnome/Kde

First of all, we will see which outputs are available, connected/disconnected with xrandr –verbose command:

black@sysbuntu:~$ xrandr –verbose

Screen 0: minimum 320 x 200, current 1280 x 800, maximum 2720 x 900

LVDS connected 1280×800+0+0 (0×4f) normal (normal left inverted right x axis y axis) 0mm x 0mm

Identifier: 0×4b

Timestamp: 12612

Subpixel: horizontal rgb

Clones:

CRTC: 0

CRTCs: 0

Transform: 1.000000 0.000000 0.000000

0.000000 1.000000 0.000000

0.000000 0.000000 1.000000

filter:

scaler: full

1280×800 (0×4f) 68.6MHz *current +preferred

h: width 1280 start 1312 end 1376 total 1406 skew 0 clock 48.8KHz

v: height 800 start 802 end 804 total 814 clock 59.9Hz

1280×720 (0×50) 74.5MHz -HSync +VSync

h: width 1280 start 1344 end 1472 total 1664 skew 0 clock 44.8KHz

v: height 720 start 723 end 728 total 748 clock 59.9Hz

1152×768 (0×51) 71.8MHz -HSync +VSync

h: width 1152 start 1216 end 1328 total 1504 skew 0 clock 47.7KHz

v: height 768 start 771 end 781 total 798 clock 59.8Hz

1024×768 (0×52) 65.0MHz -HSync -VSync

h: width 1024 start 1048 end 1184 total 1344 skew 0 clock 48.4KHz

v: height 768 start 771 end 777 total 806 clock 60.0Hz

1024×768 (0×53) 63.5MHz -HSync +VSync

h: width 1024 start 1072 end 1176 total 1328 skew 0 clock 47.8KHz

v: height 768 start 771 end 775 total 798 clock 59.9Hz

800×600 (0×54) 40.0MHz +HSync +VSync

h: width 800 start 840 end 968 total 1056 skew 0 clock 37.9KHz

v: height 600 start 601 end 605 total 628 clock 60.3Hz

800×600 (0×55) 38.2MHz -HSync +VSync

h: width 800 start 832 end 912 total 1024 skew 0 clock 37.4KHz

v: height 600 start 603 end 607 total 624 clock 59.9Hz

640×480 (0×56) 25.2MHz -HSync -VSync

h: width 640 start 656 end 752 total 800 skew 0 clock 31.5KHz

v: height 480 start 490 end 492 total 525 clock 59.9Hz

640×480 (0×57) 23.8MHz -HSync +VSync

h: width 640 start 664 end 720 total 800 skew 0 clock 29.7KHz

v: height 480 start 483 end 487 total 500 clock 59.4Hz

VGA-0 connected (normal left inverted right x axis y axis)

Identifier: 0×4c

Timestamp: 12612

Subpixel: no subpixels

Clones:

CRTCs: 0 1

Transform: 1.000000 0.000000 0.000000

0.000000 1.000000 0.000000

0.000000 0.000000 1.000000

filter:

EDID_DATA:

00ffffffffffff001e6d054bdef70400

081101036a291a78ea9bb6a4534b9d24

144f54a76f80950f81808140714f0101

0101010101019a29a0d0518422305098

360098ff1000001c000000fd00384b1c

530e000a202020202020000000fc004c

31393457540a202020202020000000fc

000a2020202020202020202020200074

load_detection: 1 (0×00000001) range: (0,1)

1440×900 (0×138) 106.5MHz -HSync +VSync +preferred

h: width 1440 start 1520 end 1672 total 1904 skew 0 clock 55.9KHz

v: height 900 start 903 end 909 total 934 clock 59.9Hz

1440×900 (0×139) 136.8MHz -HSync +VSync

h: width 1440 start 1536 end 1688 total 1936 skew 0 clock 70.6KHz

v: height 900 start 903 end 909 total 942 clock 75.0Hz

1152×864 (0×13a) 108.0MHz +HSync +VSync

h: width 1152 start 1216 end 1344 total 1600 skew 0 clock 67.5KHz

v: height 864 start 865 end 868 total 900 clock 75.0Hz

1024×768 (0×13b) 78.8MHz +HSync +VSync

h: width 1024 start 1040 end 1136 total 1312 skew 0 clock 60.0KHz

v: height 768 start 769 end 772 total 800 clock 75.0Hz

1024×768 (0×13c) 75.0MHz -HSync -VSync

h: width 1024 start 1048 end 1184 total 1328 skew 0 clock 56.5KHz

v: height 768 start 771 end 777 total 806 clock 70.1Hz

1024×768 (0×52) 65.0MHz -HSync -VSync

h: width 1024 start 1048 end 1184 total 1344 skew 0 clock 48.4KHz

v: height 768 start 771 end 777 total 806 clock 60.0Hz

832×624 (0×13d) 57.3MHz -HSync -VSync

h: width 832 start 864 end 928 total 1152 skew 0 clock 49.7KHz

v: height 624 start 625 end 628 total 667 clock 74.6Hz

800×600 (0×13e) 49.5MHz +HSync +VSync

h: width 800 start 816 end 896 total 1056 skew 0 clock 46.9KHz

v: height 600 start 601 end 604 total 625 clock 75.0Hz

800×600 (0×54) 40.0MHz +HSync +VSync

h: width 800 start 840 end 968 total 1056 skew 0 clock 37.9KHz

v: height 600 start 601 end 605 total 628 clock 60.3Hz

800×600 (0×13f) 36.0MHz +HSync +VSync

h: width 800 start 824 end 896 total 1024 skew 0 clock 35.2KHz

v: height 600 start 601 end 603 total 625 clock 56.2Hz

640×480 (0×140) 31.5MHz -HSync -VSync

h: width 640 start 656 end 720 total 840 skew 0 clock 37.5KHz

v: height 480 start 481 end 484 total 500 clock 75.0Hz

640×480 (0×56) 25.2MHz -HSync -VSync

h: width 640 start 656 end 752 total 800 skew 0 clock 31.5KHz

v: height 480 start 490 end 492 total 525 clock 59.9Hz

720×400 (0×141) 28.3MHz -HSync +VSync

h: width 720 start 738 end 846 total 900 skew 0 clock 31.5KHz

v: height 400 start 412 end 414 total 449 clock 70.1Hz

HDMI-0 disconnected (normal left inverted right x axis y axis)

Identifier: 0×4d

Timestamp: 12612

Subpixel: horizontal rgb

Clones:

CRTCs: 0 1

Transform: 1.000000 0.000000 0.000000

0.000000 1.000000 0.000000

0.000000 0.000000 1.000000

filter:

scaler: full

coherent_mode: 1 (0×00000001) range: (0,1)

DVI-0 disconnected (normal left inverted right x axis y axis)

Identifier: 0×4e

Timestamp: 12612

Subpixel: horizontal rgb

Clones:

CRTCs: 0 1

Transform: 1.000000 0.000000 0.000000

0.000000 1.000000 0.000000

0.000000 0.000000 1.000000

filter:

scaler: full

coherent_mode: 1 (0×00000001) range: (0,1)

So we see that LVDS and VGA-0 are connected (means available). I know that LVDS is my laptop’s main screen, so VGA-0 must be my secondary monitor. And it is located at the left side of my laptop. Therefore, i am executing the following command:

black@sysbuntu:~$ xrandr –output LVDS –right-of VGA-0

That’s all. Now i extend my monitor output to a secondary monitor without any logout or restart.