How to Reset NVRAM, PRAM, SMC on a Mac? How to Clear Them?

Troubleshooting Mac Startup Issues: Resetting NVRAM and SMC

Mac startup slowdowns can impact productivity. While hardware could be the culprit, resetting your Mac's NVRAM (Non-Volatile Random Access Memory) or SMC (System Management Controller) is often a simple fix. Older Macs used PRAM (Parameter Random Access Memory), but this is obsolete.

This guide explains how to reset NVRAM, PRAM (where applicable), and SMC on various Mac models.

Resetting NVRAM: Addressing Display, Sound, Bluetooth, and Startup Problems

Resetting NVRAM can resolve several issues, including:

• Display problems: Screen glitches, often caused by accidental drops or liquid spills.
• Sound issues: Audio discrepancies or complete audio loss, even after checking sound settings.
• Bluetooth connectivity problems: Inability to connect Bluetooth devices like headphones.
• Startup problems: Difficulties turning on your Mac.

M1 and M2 Macs: For these models, NVRAM typically resets automatically when problems occur. However, if issues persist, consider using the Terminal method (detailed below).

Intel Macs:

1. Shut down your Mac.
2. Turn it back on, immediately holding down Option, Command, P, and R for 20 seconds.
3. Release the keys after hearing the startup sound twice (or after the Apple logo disappears twice on Macs with the T2 security chip).

Resetting NVRAM via Terminal: (Suitable for all Macs)

1. Open Spotlight search.
2. Type "Terminal" and launch the application.
3. Type sudo nvram -c and press Enter.
4. Enter your administrator password.
5. Type sudo shutdown -r now and press Enter to restart.

Resetting SMC: Addressing Battery, Fan, and Power Issues

Resetting the SMC addresses issues like:

• Battery drain: Unexpectedly rapid battery depletion.
• Fan problems: Malfunctioning fans leading to overheating.
• Power issues: Problems with charging or power supply.

M1 and M2 Macs: SMC reset is not applicable to these models.

Intel Macs: The SMC reset process varies depending on your Mac model and whether it has a removable battery.

MacBooks with Apple T2 Security Chip (2018-2020):

1. Shut down your Mac.
2. Hold down Control, Option, and Shift keys, then press and hold the power button for seven seconds.
3. Release all keys and power on your MacBook.

MacBooks with Non-Removable Battery (Pre-2018):

1. Shut down your Mac and unplug the power adapter.
2. Hold down Shift, Control, Option, and the power button for ten seconds.
3. Reconnect the power adapter and turn on your Mac.

MacBooks with Removable Battery (Pre-2015):

1. Shut down your Mac, remove the power adapter and battery.
2. Press and hold the power button for five seconds.
3. Reinstall the battery and reconnect the power adapter.
4. Turn on your Mac.

For desktop Macs (iMacs), consider factory resetting as a last resort.

Conclusion

Resetting NVRAM and SMC is a straightforward troubleshooting step for various Mac malfunctions. While these resets often resolve issues, additional software solutions might be necessary for persistent problems.

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