How to Reset PRAM/NVRAM on a Mac

To reset PRAM/NVRAM on an Intel Mac, shut it down, turn it on, and immediately hold Option-Command-P-R for about 20 seconds. Release the keys after the Mac restarts a second time, or after the startup sound plays twice on models that use one.

This keyboard reset does not apply to Macs with Apple silicon, including M-series chips. Those Macs check NVRAM during startup and do not provide the same manual shortcut.

What does a PRAM/NVRAM reset do on a Mac?

PRAM means parameter random-access memory, while NVRAM means nonvolatile random-access memory. Both names refer to a small amount of memory that keeps certain system settings available when the Mac is turned off.

Depending on the Mac and macOS version, NVRAM may store settings related to:

• Speaker volume
• Display resolution
• Startup disk selection
• Time zone
• Recent kernel panic information used for diagnostics

A PRAM reset for Mac computers can help when one of these stored settings appears incorrect. Common examples include the wrong startup disk being selected, unexpected startup sounds, volume settings that do not behave normally, or a display resolution that changes unexpectedly.

A PRAM reset does not erase personal files, installed applications, or ordinary documents. It also does not reinstall macOS or repair every startup, sound, or display problem.

What should you do before resetting PRAM on a Mac?

1. Save open documents and close applications. The Mac must be shut down or restarted during the procedure.
2. Note settings that you may need to restore, including speaker volume, display resolution, startup disk, and time zone.
3. Confirm whether the Mac has an Intel processor or Apple silicon. Choose About This Mac from the Apple menu. An Intel model identifies its processor as Intel; an Apple silicon model lists a chip such as Apple M1, M2, M3, M4, or a later M-series chip.
4. If possible, use the Mac’s built-in keyboard or a wired keyboard. A wireless keyboard may not connect early enough during startup for the shortcut to register.
5. Disconnect nonessential external devices if you are troubleshooting startup behavior. Leave required power, display, keyboard, and mouse connections in place.

How do you reset PRAM/NVRAM on an Intel Mac?

1. Shut down the Intel Mac completely.
2. Find the Option, Command, P, and R keys before turning the Mac on. You must press all four keys together.
3. Press the power button, then immediately press and hold Option-Command-P-R. Do not wait for the login screen or desktop.
4. Keep holding the keys for about 20 seconds. The Mac may appear to restart while you hold them.
5. On an Intel Mac that plays a startup sound, release the keys after the second startup sound. On an Intel Mac that does not play a startup sound, release them after the Apple logo appears and disappears for the second time.
6. Allow the Mac to start normally, then sign in and check the setting or symptom that prompted the reset.

If the Mac starts normally without an apparent second cycle, shut it down and try again. Pressing the keys too late is a common reason a PRAM reset on Mac does not run.

If the Mac uses a firmware password, the startup shortcut may not work until that password is turned off. Use Apple’s official instructions for the Mac model instead of repeatedly attempting the shortcut.

How do you reset PRAM on an Apple silicon Mac?

There is no Option-Command-P-R procedure for Apple silicon Macs. M-series Macs check NVRAM during startup and reset it automatically when necessary, so instructions explaining how to reset PRAM on Mac with the four-key shortcut apply only to Intel models.

For an Apple silicon Mac, shut it down, wait briefly, and start it again. If the problem continues, install available macOS updates and review the affected setting in System Settings.

If the Mac cannot start normally, use macOS Recovery. Shut down the Mac, then press and hold the power button until startup options appear. Select Options and follow the onscreen prompts. Do not erase the Mac merely to address a sound, display, or startup-setting issue.

What should you check after a PRAM reset on a Mac?

After you reset PRAM on Mac, open System Settings and review any settings that may have returned to defaults.

• Confirm the intended startup disk is selected.
• Check the date, time, and time zone.
• Adjust speaker volume and sound output.
• Check display resolution, refresh rate, arrangement, and scaling.
• Reconnect external displays or audio devices and confirm the correct output is selected.

Then restart the Mac once without holding any keys. This confirms whether it can start normally with the updated settings.

What should you do if a PRAM reset does not fix the Mac?

1. Restart the Mac normally and test the problem again.
2. Install available macOS updates through System Settings.
3. Disconnect nonessential accessories and test with only required devices connected.
4. Start the Mac in safe mode to check whether software loaded during startup contributes to the problem. The safe-mode procedure differs between Intel and Apple silicon Macs, so use the instructions for the correct model.
5. Run Apple Diagnostics if the Mac repeatedly fails to start, produces unexplained shutdowns, cannot detect built-in hardware, or continues showing display or sound problems after basic checks.

A diagnostic reference code or a repeated problem with built-in hardware is a reason to contact Apple. Do not assume that one failed PRAM reset proves a hardware component has failed.

How do you get official Apple help with a PRAM/NVRAM problem?

Open {site} and choose the support section for Mac. Search for NVRAM, Mac startup problems, Apple Diagnostics, or the exact symptom you see.

Before contacting Apple Support, have the Mac model, macOS version, processor or chip type, and any Apple Diagnostics reference code ready. Explain whether the problem began before or after a macOS update, whether external devices are connected, and which troubleshooting steps you completed.