On Sun, 1 Mar 2020 16:57:18 +0000 (UTC),
bob prohaska , in
 wrote:
>  Is there some special trick that will make a Dell ST2220L HDMI
>  monitor go to sleep when using the default GL driver on Buster?
>
>  With stretch the same thing happened, but the experimental GL
>  driver put the monitor to sleep and woke it successfully. On
>  Buster, the default GL driver seems to work well enough and is
>  more stable than the (faster) experimental. But, even though
>  the blanker seems to work, the monitor stays powered on.
>
>  There are numerous reports on-line of the ST2220L refusing to
>  wake up, but I've not found any references to chronic insomnia.
>
>  I gather there are commands to put in config.txt, but it seems
>  wise to ask before tampering.

Arch has some of the best docs in the world. Some light reading when
you have insomnia:

https://wiki.archlinux.org/index.php/Display_Power_Management_Signaling

Scrolling down, we see xset commands and their descriptions:

Command                  Description
xset s off          Disable screen saver blanking
xset s 3600 3600  Change blank time to 1 hour
xset -dpms               Turn off DPMS
xset s off -dpms         Disable DPMS and prevent screen from blanking
xset dpms force off  Turn off screen immediately
xset dpms force standby  Standby screen
xset dpms force suspend  Suspend screen

But you probably need to run

xset q

to see your current settings. Thanks for the question, since I saw the
section on how to modify settings for a given tty, as some of my
servers don't blank the screen. I've been just hitting the power switch.

--
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I can please only one person per day. Today is not your day. Tomorrow
isn't looking good, either.
I am BOFH. Resistance is futile. Your network will be assimilated.

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