--- a/x.rst	Tue Mar 31 12:40:54 2015 +0300
+++ b/x.rst	Thu Apr 02 12:55:33 2015 +0300
@@ -437,3 +437,25 @@
 
   $ sudo dpkg-reconfigure x11-common
 
+Running X server without display.
+=================================
+
+Run ``Xvfb`` and make screenshort of desktop::
+
+  $ apt-get install xvfb
+  $ Xvfb :1 -screen 0 1280x1024x24 &
+  $ xclock -display :1 &
+  $ import -display :1 -window root image.png
+  $ kill %1 %2
+
+In order to run ``Xvfb`` permanently add entry to ``/etc/inittab``::
+
+  xvfb:2:respawn:/usr/bin/Xvfb :1 -ac -screen 0 1280x1024x24
+
+Running X server in nested windows.
+===================================
+::
+
+  $ sudo apt-get install xnest
+  $ startx xterm -- `command -v Xnest` :1 -geometry 800x600
+