The brightness slider is missing
Greyed out, absent from Quick Settings, or present but doing nothing. Driver checks in order of likelihood.
Brightness keys stopped working
Function keys that do nothing after a reinstall or update, and what to do when the vendor utility is gone.
Night light and eye strain
Colour temperature and backlight are two separate controls. Which one actually helps in the evening.
Tray brightness utilities
How the category works, who benefits from one, and the hardware conditions it depends on.
External monitors and DDC/CI
Enable the protocol, identify a dock that blocks it, and match brightness across mismatched panels.
Compare the methods
Five approaches side by side on what each one really controls.
Last reviewed 17 August 2026 · Published by Matthew E. Fitzpatrick · Report an error