turn off monitor by Gnome

[mfaridi]

I use
FreeBSD mfaridi.com 7.2-RELEASE-p4 FreeBSD 7.2-RELEASE-p4
and I use Gnome
when I go to power management menu and Iset my monitor should turn off after 5 minute , nothing is happen and my LCD monitor dose not turn off .
what I must do ?
how I can turn off monitor by command ?

[Beastie]

Does it support DPMS? You could add this to /etc/X11/xorg.conf:

Section "ServerFlags"
[...]
Option "OffTime" "5"
[...]
EndSection




Option "OffTime" "time"
sets the inactivity timeout for the off phase of DPMS mode.
time is in minutes, and the value can be changed at run-time
with xset(1). Default: 40 minutes. This is only suitable for
VESA DPMS compatible monitors, and may not be supported by all
video drivers. It is only enabled for screens that have the
"DPMS" option set (see the MONITOR section below).

[graudeejs]

xset dpms force off