Resetting M1 Machines

The following information is excerpted from MacWorld.co.uk.

Resetting NVRAM on M1 Mac
In November 2020, Apple launched its first Mac with the M1 Chip. With Apple’s new system it is not possible to reset the NVRAM.

Unlike SMC, which no longer exists on M1 Macs, NVRAM exists, but it works differently.

The new Macs still have a kind of parameter memory whose settings you can view and change with the terminal command NVRAM, but there is no longer any command to reset the contents of NVRAM.

According to several sources, including the accessory manufacturer Caldigit and comments on Apple's support forum, which claims to have talked to Apple's support, the M1 processor tests NVRAM when the computer is started from shutdown (i.e. not after a normal reboot). If something is wrong with the memory, it is reset automatically.

[NOTE: After a full shutdown, wait at least 10 seconds before powering back up.]

We have so far not been able to test whether this means that the M1 Macs can "save themselves" from incorrectly set NVRAM values. We recommend that you take extra care if you make manual changes with the NVRAM tool.

An alternative [to performing an NVRAM reset] is to start the Mac in recovery mode, [then] start Terminal from the Tools menu and [then] enter the command:

NVRAM -c

How to start M1 Mac in Recovery Mode
If you have a new Mac with an Apple processor, such as the M1 Macs introduced in November 2020, you need to enter Recovery a different way [than is done with an Intel Mac].

  • Turn off the Mac. [and wait 10 seconds]

  • Press the on button and keep it pressed.

  • Eventually the Apple logo will appear with text below it informing that if you continue holding the power button you will be able to access startup options. Keep pressing that button.

  • Eventually you will be able to select Options > Continue, and this will open up Recovery.

There is also a so called 'fallback recovery mode', that is detailed by Apple here. In this case you double press the power button: first press it, release, and then press and hold down the power button.


Fallback recovery mode accesses a second copy of the recoveryOS on the SSD of the Macs with M1 Chip. Apple says the second copy is there for resiliency.

https://www.macworld.co.uk/how-to/reset-nvram-mac-3801373/

https://www.macworld.co.uk/how-to/mac-recovery-mode-3674052/



John R. Carter, Sr.