My desktop computer suddenly started looking darker and the colors seem grey or washed out. I can't adjust the brightness through Windows because this isn't a laptop. At the same time, my wallpaper disappeared and became completely black, although the desktop icons were still visible. Restarting brought the wallpaper back, but the dim-looking display remains. I wasn't running anything unusual or putting the system under heavy load. What should I check?
3 Answers
Since this is a desktop monitor, check the monitor’s own on-screen menu rather than Windows brightness controls. Look at the brightness and contrast settings, since a button press or brief power interruption may have changed them. It’s also worth unplugging and reconnecting the display cable in case the connection is loose.
Check Windows display settings for Night Light or any automatic color or brightness feature. Night Light can make the screen look noticeably dull or washed out. You can also open Device Manager, expand Monitors, and make sure your monitor hasn’t been disabled.
The black wallpaper is probably separate from the dim display. Go to Personalization, then Background, and select the wallpaper again. If it’s already selected but doesn’t appear, open Task Manager and restart Windows Explorer to reload the desktop shell. A reboot restoring the wallpaper points more toward a temporary Windows desktop issue than a monitor failure.

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