Settings like sound volume, display resolution, startup disk selection, time zone, and recent kernel panic information are stored in NVRAM/PRAM. PRAM, which is also known as Parameter RAM, does the same thing with NVRAM. It is a small amount of memory for your Mac to save some settings and access them quickly. The full name of NVRAM is nonvolatile random-access memory. If you are using MacBook Pro, you should use the Touch Bar on the keyboard to change the brightness. You can use them to change the screen brightness.

There are two brightness keys on your Mac keyboard. You can do this job using your Mac keyboard. To rule out this possibility, you can change your Mac display’s brightness to have a try. You may have adjusted the screen brightness to dark without knowing it. If your Mac screen still has no response, you can try the next solution. Or you can press the Control-Command key and then press the Power button. To force restart a Mac, you need to press and hold the Power button for seconds. You can force restart your device to have a try. If you are sure that the power supply is normal but the MacBook black screen of death issue persists, there may be some temporary issues on your Mac. Method 2: Force Restart Your Mac Computer If you are using a MacBook Air or MacBook Pro, you can charge your device and then press the Power button to see whether it can boot normally. You can check the power outlet to see whether the power supply is normal. When your Mac computer goes to a black screen, the first thing you need to do is to check the power for your device. Restore your Mac from a Time Machine backup.Use Disk Utility to repair your startup disk.

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