Anleitung: SMC-Reset und PRAM-Reset am Mac durchführen

The following guides explain how to perform an SMC or NVRAM/PRAM reset on various Mac models: iMac , MacBook Pro, MacBook Air, Mac Pro , Mac Mini and Mac Studio. The terms PRAM and NVRAM reset are used interchangeably, although in this article we will use the more common term PRAM.

SMC reset not possible on Apple Silicon Macs

A brief note for owners of M1 Macs: The new Apple Silicon Macs no longer have an SMC chip and accordingly you cannot perform an SMC reset there. To achieve a similar effect, however, you can use these alternatives to the SMC reset .

What are PRAM, NVRAM and SMC?

The abbreviations PRAM and NVRAM stand for the terms "Parameter RAM" and "Non Volatile RAM". This is a type of cache that contains information that persists across Mac restarts. This can be, for example, the start volume, the brightness of the display, the set resolution or similar.

The abbreviation SMC, on the other hand, stands for "System Management Controller" and refers to a chip that contains the Mac's firmware. The SMC stores charging parameters, power management settings, fan control settings, WiFi data, and more.

In rare cases, for example with macOS updates, incorrect data can be written to this cache. As a result, there are problems with loading, with the WLAN connection or other strange behavior on the Mac. Many of these things can be resolved by SMC or PRAM resets.

PRAM reset on Intel Macs and Apple Silicon Macs

The PRAM is reset on Intel Macs as follows:

  1. Reboot Mac
  2. hold down the keys CMD + ALT + P + R right after the start
  3. Hold the keys down until the Mac starts up
  4. release keys

This completes the PRAM reset and the Mac can boot normally.

Since Apple Silicon Macs no longer offer an option to clear the PRAM, you have to choose an alternative, which is described here .

SMC reset for Macs with T2 chip (from late 2017)

MacBook Pro models with Touch ID and other Macs released after late 2017 were equipped with a security chip (T2 chip). An SMC reset is carried out on these Macs as follows:

  1. Turn off Mac
  2. Wait 10 seconds to make sure it has completely shut down
  3. Press and hold the power button for about 10 seconds
  4. Release the switch and restart Mac

This clears the Mac's SMC memory.

SMC reset on Macs before 2018

For older Macs built before 2018, proceed as follows to reset the SMC. Basically, it always comes down to the Mac being without power for about 30 seconds, as this will erase the SMC.

SMC reset on iMac, Mac Mini and Mac Pro

  1. shut down mac
  2. unplug the power cord
  3. wait about 30 seconds
  4. Plug in the power cord again

SMC reset on MacBook Pro, MacBook Air and MacBook

For very old models where you can still remove the battery, the reset works as follows:

  1. shut down mac
  2. Unplug the power cord from the Mac
  3. Remove battery from MacBook
  4. Press and hold the power button for about 5 seconds
  5. Reinstall the battery

For models with a permanently installed battery, the SMC reset is as described here:

  1. unplug the power cord
  2. hold down the following keys at the same time: SHIFT + CTRL + ALT + power