display_off

Powers off all DDC/CI capable displays on Windows shutdown.

Installation

1. Download display_off.exe binary from Releases
2. Move the binary to any folder, i.e. C:\Program Files\display_off
3. Execute once for a test. All the monitors should shut off.
4. Open Task Scheduler, create an event with a custom event trigger. After creating a task, go Triggers > New > Custom > Edit Event > XML and paste the following (mind the NOTICE below):

<QueryList>
  <Query Id="0" Path="System">
    <Select Path="System">
    *[System[Provider[@Name='User32'] and (Level=4 or Level=0) and (EventID=1074)]]
   and 
     *[EventData[Data[@Name='param5'] and (Data='power off')]]
    </Select>
  </Query>
</QueryList>

5. Enable Run with highest privileges and save the task

Notice for non-English Windows locales

power off text in the XML will be different for each Windows locale. In order to find out the exact text:

1. Open Event Viewer, then Windows Logs > System
2. Filter for EventID 1074
3. Find a relevant event (RuntimeBroker.exe, 0x0), then in Details tab -> XML View
4. Copy the exact text from param5 and paste in XMP above

Credits

• @manvir-singh for writing an initial code
• Ste from Superuser forum for an XML trigger example