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I want the opposite of what seemingly everybody else wants: on my plain old character mode tty1 console directly served by the video card of my bare metal Debian 8.10 Jessie box, I want the screen blanker to go to either DPMS "Suspend" or "Off". Whichever will kill the video signal that keeps my Acer monitor thinking there's something to display, therefore the monitor never truly goes to power save mode on that input.

I see many answers regarding Gnome and X-Windows, but this is not the windowing environment.

Plus, I want it to sleep/suspend/turn off rather than prevent this mode. See, the Acer monitor has 3 video inputs so I have the linux box feeding the DVI input (rarely looked at) while the DisplayPort comes from the desktop machine running some Brand-X operating system for 99% of my usage. But when my desktop sleeps, the Acer switches over to the DVI input from the linux box automatically, forcing me to switch the Acer monitor back to DisplayPort manually.

If I could get the linux box to shut off its video signal completely, the display would just go to sleep when both machines blank their video outputs and show my desktop machine's video when I wake it up. So far everything I've tried comes up a dead-end.

Debian 8.10 Jessie (about 1 week old)
Dell OptiPlex 980 (circa 2010)
ATI Radeon HD 4550 video card
systemd init system

uname -a
Linux bcfs 3.16.0-4-amd64 #1 SMP Debian 3.16.51-3 (2017-12-13) x86_64 GNU/Linux

Thanks.

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2 Answers 2

Reset to default
1

You can do this with setterm.

setterm --powerdown 10

will power the screen down after ten minutes’ inactivity, and

setterm --powersave powerdown

will power it down immediately.

setterm is part of the util-linux package in Debian, so it’s always present.

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  • I had forgotten about setterm and found no references to it in my search. While some options had immediate effect (such as --reverse), none of the --powersave options had any effect. I saw nothing in grub that would affect this, either. Puzzling. Thanks though!
    – Bote Man
    Commented Mar 23, 2018 at 21:00
  • Curiously, setterm --powerdown 1 >> /dev/tty1 does indeed blank the screen, but it does not power down the display. setterm --powersave powerdown >> /dev/tty1 results in setterm: cannot (un)set powersave mode: Inappropriate ioctl for device
    – Bote Man
    Commented Mar 24, 2018 at 4:34
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Per https://stackoverflow.com/a/8645274/1992102

vbetool satisfied my need as expressed in this question.

apt-get install vbetool

vbetool dpms off turns off the display, KEYBOARD WILL NOT WAKE THE DISPLAY, you must issue "on" from any terminal to turn it back on

vbetool dpms on enables the display

This is ideal for a headless server that sees only occasional use of its built-in display.

It seems that linux core developers do not want us messing with the console video adapters, as it is incredibly difficult to change their behavior.

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