DPMS
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Display Power Management Signaling
A VESA interface standard that defines four power management modes for monitors in idle state:
- on
- stand-by
- suspend
- off.
Using DPMS, the display controller (typically the video card or chip from which the monitor receives signals) sends a signal along two signal lines to the monitor, instructing it to enter into one of the four power management states. Those two lines are the horizontal sync (h-sync) and vertical sync (v-sync) lines.
Linux X11
As of Xorg 1.8 DPMS is auto detected and enabled if ACPI is also enabled at kernel runtime.