dpms — VESA BIOS DPMS driver

       The  VESA  BIOS  DPMS  calls  do  not  provide  any  way  to  identify a particular display or adapter to
       manipulate.  As a result, this driver may have unexpected  results  on  systems  with  multiple  displays
       and/or adapters.

Debian                                           August 23, 2008                                         DPMS(4)

       The  dpms  driver  uses  the VESA BIOS to manage an external display during suspend and resume.  When the
       machine suspends, the dpms driver turns the external display off.  When the machine resumes, it  restores
       the display to its state when the driver was first loaded.

       dpms — VESA BIOS DPMS driver

acpi_video(4)

devicedpms