It’s never pleasant to see your Mac’s screen suddenly become distorted, frozen, or won’t turn on. Unlike other Mac issues, you can’t put off dealing with a malfunctioning screen; it must be addressed immediately. If you’re lucky, the glitch is just a glitch, temporary, and not necessarily indicative of ongoing problems. In many cases, screen issues don’t return after a reboot.

Assuming that the problem you are experiencing is actually a graphics issue and not one of the startup issues that manifest as a gray screen, blue screen, or black screen, it is a good idea to take the time to go through these troubleshooting tips.

You’d be surprised how often you can fix issues like display problems by simply turning your Mac off and back on. Restarting your Mac resets everything to a familiar state. It clears both system and graphics RAM, resets the graphics processing unit (GPU) and central processing unit (CPU), and then restarts everything in orderly steps.

This may seem like a no-brainer, but if you’re using a separate display—one that isn’t built into your Mac—you should check to make sure it’s turned on, the brightness is turned up, and that it’s properly connected to your Mac. You might laugh at the idea of a cord coming loose or the power somehow being turned off, but kids, adults, and pets have all been known to accidentally unplug a cord or two, hit a power button, or step on a power strip switch.