NVRAM Error on Mac: How to Reset and Fix Issues

What is an NVRAM Error

An NVRAM error on a Mac occurs when data in non-volatile RAM (NVRAM) becomes corrupted or inconsistent. NVRAM stores critical system settings such as the startup disk selection, sound volume, time, display information, and other parameters. When this data is damaged, a Mac may exhibit various symptoms:

• The Mac doesn't remember time or sound settings after a restart.
• The display is incorrectly detected or doesn't appear.
• Problems selecting the startup disk.
• The Mac gets stuck on the startup screen or fails to boot completely.
• Wi-Fi or other peripheral devices malfunction.

An NVRAM error isn't always accompanied by an explicit message, but the symptoms indicate a need to reset the parameters.

Common Causes

NVRAM issues typically arise from the following causes:

1. Improper shutdown or power failure – sudden power loss or a forced reboot can corrupt NVRAM data.
2. Outdated firmware or conflicting settings – after a macOS update or third-party software installation, NVRAM settings may become incompatible.
3. Hardware malfunction – a rare case where the NVRAM chip or related components fail.
4. Incorrect manual changes via Terminal – if a user manually modifies NVRAM values using the nvram command, errors can occur from invalid input.

Solutions

Method 1: Reset NVRAM on Intel-based Mac

This is the standard method for Macs with Intel processors (models released before 2020). Resetting NVRAM restores default settings.

1. Shut down your Mac completely. Click the Apple menu () and select "Shut Down...", or hold the power button for 10 seconds if the Mac is unresponsive.
2. Turn on your Mac and immediately press and hold the key combination: Option (Alt) + Command (⌘) + P + R.
3. Hold the keys for about 20 seconds. On Macs with a T2 chip (2018 and newer), you may hear a second startup chime – this is normal.
4. Release the keys and wait for the startup process to complete. NVRAM will now be reset.

⚠️ Important: After the reset, you may need to reconfigure certain settings, such as the startup disk selection (hold the Option key at startup), sound volume, time, and display settings.

Method 2: Reset NVRAM on Apple Silicon Macs (M1, M2 and newer)

On Macs with Apple Silicon processors, NVRAM is reset via Recovery Mode:

1. Shut down your Mac completely.
2. Enter Recovery Mode: Press and hold the power button until the startup menu appears, then select "Options" and click "Continue".
3. In the Utilities menu, select "Reset NVRAM". If this option isn't available, select "Erase All Settings" instead, but be aware this will erase all data – use this only if other methods fail.
4. Confirm the reset and restart your Mac.

💡 Tip: NVRAM issues are rare on Apple Silicon. If symptoms persist, check for macOS updates or contact Apple Support.

Method 3: Reset NVRAM via Terminal (Optional)

If the key combination doesn't work, you can reset NVRAM through Terminal. This method requires administrator privileges.

1. Open Terminal (via Finder → Utilities or Spotlight).
2. Enter the command: sudo nvram -c
3. Enter your administrator password when prompted.
4. Restart your Mac with the command sudo reboot or via the Apple menu.

⚠️ Caution: The nvram -c command deletes all custom NVRAM settings. Ensure you know the administrator password. This command may not work on Apple Silicon Macs.

Prevention

To minimize the risk of NVRAM corruption, follow these recommendations:

• Avoid forced shutdowns – always shut down your Mac properly via the Apple menu.
• Keep macOS updated regularly – newer system versions fix known vulnerabilities.
• Be cautious with the nvram command – only modify parameters if you are certain of their purpose.
• Use an Uninterruptible Power Supply (UPS) – to protect against power outages.
• Perform periodic hardware checks – use Apple Diagnostics if symptoms appear.

For Apple Silicon Mac models, NVRAM issues are minimal due to the architecture, but general usage guidelines still apply.