How to Reset SMC and NVRAM on Mac to Fix Hardware Issues

When your Mac starts experiencing bizarre hardware problems—such as the battery not charging correctly, the fans running at maximum speed for no reason, or the screen resolution constantly resetting—a simple reboot often is not enough to fix the issue. In these situations, the most effective troubleshooting step is to reset two low-level hardware controllers: the System Management Controller (SMC) and the Non-Volatile Random-Access Memory (NVRAM).

Resetting these components clears out corrupted hardware settings and forces your Mac to re-establish connections with its internal hardware. It is a completely safe procedure that will not delete your personal files, applications, or documents.

What Are the SMC and NVRAM?

Before proceeding, it is helpful to understand what you are actually resetting:

• System Management Controller (SMC): This is a dedicated chip on the Mac logic board responsible for low-level physical functions. It manages battery management, thermal management (fans and temperature sensors), keyboard backlighting, power button responses, and sleep/wake functionality.
• NVRAM (formerly PRAM): This is a small amount of memory that your Mac uses to store certain settings in a location it can access very quickly before the operating system even boots. It stores your speaker volume, screen resolution, startup disk selection, and recent kernel panic information.

Important: Apple Silicon vs. Intel Macs

The instructions for resetting the SMC and NVRAM are entirely dependent on which processor your Mac uses. You must determine whether you have a newer Apple Silicon (M1, M2, M3) Mac or an older Intel-based Mac.

1. Click the Apple Logo in the top left corner of the screen.
2. Select About This Mac.
3. Look at the information displayed. If it says “Chip: Apple M1” (or M2/M3), you have an Apple Silicon Mac. If it says “Processor: Intel Core i5” (or similar), you have an Intel Mac.

How to Reset NVRAM and SMC on Apple Silicon Macs

If you have an Apple Silicon Mac, you do not need to memorise any complex keyboard combinations. Apple has dramatically simplified the architecture of these newer machines.

There is no SMC or NVRAM reset button on an Apple Silicon Mac.

Instead, the Mac automatically tests and resets these hardware controllers every time it boots up from a completely powered-off state. If your Apple Silicon Mac is experiencing hardware issues, simply follow these steps:

1. Click the Apple Logo and select Shut Down.
2. Wait at least 30 seconds to ensure the machine has completely powered down.
3. Press the power button to turn the Mac back on.

The system will automatically perform any necessary hardware resets during the boot sequence.

How to Reset the NVRAM on Intel Macs

If you are using an older Intel Mac, the NVRAM must be reset manually using a specific keyboard shortcut during the boot process.

1. Shut down your Mac completely.
2. Locate the following four keys on your keyboard: Option, Command, P, and R.
3. Press the power button to turn on your Mac.
4. Immediately press and hold the Option + Command + P + R keys simultaneously.
5. Keep holding the keys for about 20 seconds. During this time, your Mac might appear to restart.
6. If your Mac plays a startup chime, release the keys after you hear the second chime.
7. If your Mac has an Apple T2 Security Chip (typically 2018 or newer Intel models), release the keys after the Apple logo appears and disappears for the second time.

Once your Mac finishes booting, you may need to open System Settings to re-adjust your speaker volume or screen resolution, as these will have returned to their factory defaults.

How to Reset the SMC on Intel Macs (Laptops)

The procedure for resetting the SMC on an Intel MacBook depends on whether or not it has the Apple T2 Security Chip.

For Intel MacBooks with the T2 Chip (2018 and newer):

1. Shut down your Mac.
2. On your built-in keyboard, press and hold the following keys: Control (left side) + Option (left side) + Shift (right side).
3. Keep holding all three keys for 7 seconds. Your Mac might turn on.
4. While still holding those three keys, press and hold the Power Button as well.
5. Keep holding all four keys for another 7 seconds, then release them.
6. Wait a few seconds, then press the power button to turn your Mac on.

For older Intel MacBooks (without the T2 chip):

1. Shut down your Mac.
2. On your built-in keyboard, press and hold Shift + Control + Option (on the left side of the keyboard).
3. While holding those three keys, press and hold the Power Button.
4. Keep holding all four keys for exactly 10 seconds.
5. Release all keys, then press the power button to turn your Mac on.

How to Reset the SMC on Intel Desktop Macs (iMac, Mac mini, Mac Pro)

Resetting the SMC on an Intel desktop Mac is much simpler because it relies on physically disconnecting the power source.

1. Shut down your Mac.
2. Unplug the power cord from the wall outlet or the back of the computer.
3. Wait exactly 15 seconds.
4. Plug the power cord back in.
5. Wait exactly 5 seconds.
6. Press the power button to turn your Mac on.