The short version
- 01Record whether the screen goes black only after inactivity or during active use.
- 02For idle-only blackouts, review Windows Power & battery screen and sleep timeouts.
- 03For active-use failures, compare a direct display connection without the dock or adapter.
- 04Secure the video cable and test another cable or video output port.
- 05Press Windows + Ctrl + Shift + B to reset the graphics driver, then compare a restart.
- 06If the fault began after an update, use the documented display-driver rollback and record a second-computer test.
Likely causes
- Windows screen-off or sleep timers trigger while the computer is idle.
- The cable, dock, output port or display driver interrupts an established connection.
Does the blackout follow an idle interval?
Our first check is whether a key or mouse movement restores the screen after a consistent idle interval. Windows 11's Settings > System > Power & battery > Screen, sleep, & hibernate timeouts separately controls screen-off and sleep timing, with battery and plugged-in settings. Review those values before treating an idle transition as a hardware failure.
If it happens while working, compare the video path
Microsoft's external-display checks remove docks and adapters, secure or replace the cable, try another output and test the monitor with another computer. Our recommendation is to keep the same workload for each comparison and note which change affects the blackout.
Check the driver when an established setup stops working
Microsoft lists Windows + Ctrl + Shift + B and a restart for a previously working display. If the failure began after a graphics update, its rollback path is Device Manager > Display adapters > Properties > Driver > Roll Back Driver. Retain the timing and hardware comparisons for support.
Sources and review notes
Checked on . Based on Microsoft's Windows power and external-display guidance. Idle-versus-active timing and consistent comparison tests are editorial diagnostics. This reference covers Windows-connected monitors, not an unexplained black picture on a TV. Glitchary is independent of Microsoft.