Want to use that extra screen for a little more real estate, even without any cords or cables? Here's how.

You can change your Windows 10 login screen through your device's Settings app, and make it display any photo you like.

You can change the lock screen on your Windows computer by customizing the background image and specifying what supplemental information it displays.

A reader's El Capitan installation started blacking out one monitor when he's using apps full screen.