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I currently have an nvidia gtx470 with 2 x 22" 1920x1080 displays on twinview.

Since I have a spare laptop (old but works) and screen (22" 1680x1050).

A vnc server would be set up (viewonly) to the virtual screen and the laptop would login (viewonly) so its just a screen... The virtual screen would be part of my gnome session... and in theory make me a triple display setup, I've seen it done in windows... what is holding us?

Since I'm not all to experienced with vnc or xorg.conf (only just learning the settings, Can someone give me directions how to make a virtual screen/monitor and what vnc server allows for connecting to a certain screen. (realvnc does this in windows...)

I hope one of you can help Grtz, Dutchy

Edit: My Current work around is to just use unity and vnc into VMware workstation machines... alltough this kinda gets done some of the stuff I need, I would still like to have an actual third monitor

share|improve this question
I would strongly suggest taking a look at Synergy. – Nathan Osman Oct 17 '11 at 5:21
+1 to George Edison's recommendation. – RobotHumans Oct 22 '11 at 1:24
I'm confused by youracceptance of the only answer to this question. That will not add a second/third/n-th "virtual" screen to your existing X display, accessible to a VNC server (which I think is what you ask for). It will instead let you connect to a single display over VNC. I think you (and I) need somethink more like this:… – Esteban May 3 '15 at 18:39
up vote 2 down vote accepted

There is a vnc module for X that can be installed which will provide the native :0 X display when connecting remotely with the vncviewer.

  1. Install the "vnc4server" package (universe). This will provide "/usr/lib/xorg/modules/extensions/" (The module for VNC 4.1.2 was changed from to

  2. Add "vnc" to the Module section in /etc/X11/xorg.conf

    Section "Module"
        Load "vnc"
    • If your VNC server is running in a secure environment, you can disable authentication with the following configuration:

      Section "Screen"
          Option "SecurityTypes" "None" 
    • If your VNC server is NOT running in a secure environment, you will need to set a VNC password using the vncpasswd program:

      # vncpasswd

      Then tell the VNC module where the password is stored in xorg.conf:

      Section "Screen"
          Option "SecurityTypes" "VncAuth"
          Option "UserPasswdVerifier" "VncAuth"
          Option "PasswordFile" "/root/.vnc/passwd"

Logout and restart X (Ctrl-Alt Backspace)

The Source

share|improve this answer
xorg.conf no longer exists. Modify the answer to up-to-date X, please. – Oxwivi Oct 22 '11 at 9:36
@Oxwivi: what do you mean "no longer exists"? X can run without xorg.conf but if it is present it'll be taken into account. – Sergey Oct 22 '11 at 11:54
@Sergey Yes it does not exist normally now, and since there's no reason for it to exist already, we answer the question assuming it's not there. Unless, of course, the OP says he already does have xorg.conf. – Oxwivi Oct 22 '11 at 12:09
Unfortunately I can't downvote yet :) but this doesn't answer the question. Or I got it totally wrong. – Esteban May 3 '15 at 18:39

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