Display Power Management Signaling
DPMS (Display Power Management Signaling) enables power saving behaviour of monitors when the computer is not in use. The time of inactivity before the monitor enters into a given saving power level, standby, suspend or off, can be set as described in DPMSSetTimeouts(3). Note that DPMS was developed for CRT monitors, and on LCD displays, there is normally no difference between the standby, suspend and off modes.
Setting up DPMS in X
Add the following to a file in /etc/X11/xorg.conf.d/
in the Monitor
section:
Option "DPMS" "true"
Add the following to the ServerFlags
section, change the times (in minutes) as necessary:
Option "StandbyTime" "10" Option "SuspendTime" "20" Option "OffTime" "30"
"OffTime"
option does not work, use screen blanking instead, which will keep the monitor turned on with a black image. Alternatively, change "blanktime"
to "0"
to disable screen blanking
Option "BlankTime" "30"
To disable DPMS, change /etc/X11/xorg.conf.d/10-monitor.conf
as below:
Section "Monitor" Identifier "LVDS0" Option "DPMS" "false" EndSection Section "ServerFlags" Option "StandbyTime" "0" Option "SuspendTime" "0" Option "OffTime" "0" Option "BlankTime" "0" EndSection Section "ServerLayout" Identifier "ServerLayout0" EndSection
Modify DPMS and screensaver settings with a command
It is possible to turn off your monitor with the xset command which is provided by the xorg-xset package.
Examples:
Command | Description |
---|---|
xset s off |
Disable screen saver blanking |
Change blank time to 1 hour | |
Turn off DPMS | |
Disable DPMS and prevent screen from blanking | |
Turn off screen immediately | |
Standby screen | |
Suspend screen |
To query the current settings:
$ xset q
... Screen Saver: prefer blanking: yes allow exposures: yes timeout: 600 cycle: 600 DPMS (Energy Star): Standby: 600 Suspend: 600 Off: 600 DPMS is Enabled Monitor is On
See xset(1) for all available commands.
DPMS interaction in a Linux console with setterm
The setterm utility issues terminal recognized escape codes to alter the terminal. Essentially it just writes/echos the terminal sequences to the current terminal device, whether that be in screen, a remote ssh terminal, console mode, serial consoles, etc.
setterm Syntax: (0 disables)
$ setterm --blank [0-60|force|poke] $ setterm --powersave [on|vsync|hsync|powerdown|off] $ setterm --powerdown [0-60]
Pipe the output to a cat to see the escapes
$ setterm --powerdown 2>&1 | exec cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"
Pipe the escapes to any tty (with write/append perms) to modify that terminal
$ setterm --powerdown 0 >> /dev/tty3
Bash loop to set ttys 0-256
$ for i in {0..256}; do setterm --powerdown 0 >> /dev/tty$i; done; unset I;