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If the monitor is black:
Make sure the display cable is connected securely to the desktop, laptop, or dock by unplugging both ends and firmly reseating them.
Check the power cord to make sure it is plugged in securely on both ends.
Check that the power button is lit.
Check the Multiple displays setting (Settings > System > Projecting to this PC) to make sure nothing is being projected.
If the monitor is showing “No VGA (or some other) Cable”, check the Input using the monitor buttons (varies from monitor to monitor). Change the setting to Auto.
If the monitor shows “Entering Power Save Mode”, unplug the monitor from the computer for a couple of minutes and plug it back into the computer. Make certain that all connections are tight at both ends.
If brightness or contrast is off/odd, make changes using the menu (use monitor buttons, varies per monitor model).
If the scale or resolution seem off, on the computer: go to Settings > System > Display. Make sure “Change the size of text, apps, and other items” and Display resolution are both at the “Recommended” setting.
If the monitor is blurry and/or color oddness, check all cords to make sure they are secure.
If all the above have failed, try a different display port on the back of the computer. An adapter might be needed.
Indications that you need a new monitor:
The monitor comes up then fades after being turned on
There are “ghost” colors
Lines on monitor
The monitor doesn’t power up at all, even after attempting the above steps
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