The reset PRAM and NVRAM in Mac can help you solve different types of problems in no time. In this short but interesting article, I will explain in detail how to do it correctly.
Before starting with the practical part, however, I think it is right to provide you with some useful information on what the Mac PRAM is and how it works.
PRAM (Parameter Random Access Memory) is in some ways similar to RAM. Unlike RAM, it does not reset when you restart or shut down your computer. This is because it is constantly powered by a small battery on the motherboard. The PRAM is used by macOS to store various system information, such as volume level, display brightness, or screen resolution.
NVRAM and PRAM are the same thing. In fact, it is always non-volatile RAM, which means that the settings do not change when the computer is restarted or shut down. NVRAM is, therefore, nothing more than an updated PRAM terminology.
Even on Windows PCs, there is non-volatile RAM, and it is called CMOS RAM. Again, the memory is constantly powered by a battery present in the motherboard.
In the case of Windows desktop PCs, to reset the CMOS, it would be enough to open the case and disconnect the backup battery for a few seconds or act on the CMOS PIN. On Macs, on the other hand, you will have to perform a simple procedure, using a combination of keys during macOS startup or using the Terminal.
What the PRAM reset works on and when to do it
The PRAM reset acts on various aspects of the MAC :
- Startup disk
- Disk cache
- RAM
- Swap memory
- Display refresh rate
- Screen resolution
- Display brightness level
- Audio volume
- Mouse and trackpad settings
- Keyboard
- Default system font
- Kernel Panic Information
The PRAM reset must be performed when :
- Mac does not start up properly
- Mac won’t shut down
- Devices connected to the Mac are not recognized
- The monitor is not working well
- Hard drives are not working properly
- Bluetooth is not working
- System settings reset automatically
How to reset PRAM or NVRAM
The PRAM reset is very simple to carry out. You can perform it in two ways: via the start command or using the Terminal. In the following paragraphs, I show you both procedures in detail.
Reset PRAM with start command
To reset the PRAM via the start command, the procedure to perform is as follows:
- Turn off the Mac;
- Press the access key, and immediately after holding down the keys CMD + ALT + P + R ;
- Hold down the keys until the Mac beeps to start twice (on newer Macs, the Apple logo will appear and then disappear).
Reset PRAM via Terminal
If you prefer to use the Terminal, here is the procedure for performing a PRAM reset:
- Close all open applications on the Mac;
- Press CMD + SPACE, type “Terminal,” and press ENTER ;
- In the terminal window, type “sudo nvram -c” and press ENTER ;
- Type your Mac password;
- Now type the following command “sudo shutdown -r now” and press ENTER.
At this point, the Mac will restart and the PRAM reset.