FreeBSD 11.1, Xfce, and laptop screen and external monitor resolution

[David Christensen]

freebsd-questions:

I have a Dell Inspiron E1505 laptop with an Intel T7400 CPU, 2 GB RAM, 
16 GB SSD, Intel GM945 graphics, a 1280x800 screen, and a fresh install 
of FreeBSD:

[root at tinkywinky ~]# freebsd-version
11.1-RELEASE

[root at tinkywinky ~]# uname -a
FreeBSD tinkywinky 11.1-RELEASE FreeBSD 11.1-RELEASE #0 r321309: Fri Jul 
21 02:08:28 UTC 2017 
root at releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64


I have installed xorg.  'startx' seems to work correctly.


I have installed xfce and created a machine-id per the installation 
messages:

     [root at tinkywinky ~]# dbus-uuidgen --ensure

     [root at tinkywinky ~]# ls -A /var/lib/dbus/
     machine-id

When I run 'startxfce4', Xfce starts with a resolution of 1024x768. 
Applications Menu -> Settings -> Display offers two choices: 1024x768 
and 800x600.  How do I set the Xfce resolution to 1280x800 when driving 
the laptop screen?


If I connect an external 1920x1080 monitor to the VGA port of the laptop 
and press the Fn+F8 (CRT/LCD) hot key at the GELI prompt, the video 
signal is sent to the external monitor (laptop screen goes dark).  (I 
then close the laptop screen.)  'startxfce4' results in Xfce with a 
resolution of 1600x1200.  Display offers choices of 1600x1200, 
1280x1024, 1024x768, 800x600, and 640x480.  How do I set the Xfce 
resolution to 1920x1080 when driving the external monitor?


David