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

If your Mac is exhibiting strange hardware behaviour—such as the battery refusing to charge, the cooling fans spinning at maximum speed for no reason, or the screen resolution suddenly changing—a software restart is unlikely to fix the problem. Instead, you need to perform two fundamental troubleshooting steps: resetting the SMC (System Management Controller) and the NVRAM (Non-Volatile Random-Access Memory).

These small memory chips manage low-level physical functions before macOS even loads. Resetting them forces the hardware to recalibrate, which resolves a surprisingly high percentage of mysterious Mac glitches.

What Do the SMC and NVRAM Actually Do?

Understanding what these components control helps you identify when a reset is necessary.

• The SMC (System Management Controller): This chip manages physical components like power distribution, battery charging, thermal management (fans), keyboard backlighting, and the sleep/wake sensors.
• The NVRAM (Non-Volatile RAM): This small amount of memory stores settings that the computer needs to access incredibly quickly during startup, such as sound volume, display resolution, startup disk selection, and kernel panic information. (On older Macs, this was called PRAM).

Does Your Mac Have Apple Silicon or an Intel Processor?

The method you use to reset these components depends entirely on the type of processor inside your Mac. Apple completely changed the architecture when they transitioned away from Intel.

1. Click the Apple Logo in the top-left corner of your screen.
2. Select About This Mac.
3. Look at the line labelled “Chip” or “Processor”. If it says “Apple M1”, “M2”, or “M3”, you have an Apple Silicon Mac. If it says “Intel Core i5”, “i7”, or “i9”, you have an Intel Mac.

How to Reset the SMC and NVRAM on Apple Silicon (M-Series) Macs

If you have a modern Mac powered by an Apple Silicon chip, the process is incredibly simple: there is no manual reset process.

Apple integrated the functions of the SMC and NVRAM directly into the M-series system-on-a-chip. To force these systems to reset and recalibrate, you simply need to restart the computer.

1. Click the Apple Logo.
2. Select Shut Down and wait for the machine to turn off completely.
3. Close the lid (if it is a MacBook) and wait 30 seconds.
4. Turn the Mac back on. The hardware management systems will automatically verify and reset themselves during the boot process.

How to Reset the NVRAM (or PRAM) on an Intel Mac

If your Intel Mac is suffering from volume issues or blinking question marks on startup, you should reset the NVRAM.

1. Shut down your Mac completely.
2. Locate the following four keys on your keyboard: Option, Command (⌘), P, and R.
3. Turn on your Mac and immediately press and hold these four keys simultaneously.
4. Keep holding the keys for about 20 seconds.
5. During this time, your Mac will appear to restart. If your Mac plays a startup chime, you can release the keys after you hear the second chime. If your Mac has a T2 Security Chip, release the keys after the Apple logo appears and disappears for the second time.

How to Reset the SMC on an Intel Mac

If the NVRAM reset did not solve your issue, especially if it is power or thermal-related, you should reset the SMC.

For Intel MacBooks with the T2 Security Chip (2018–2020):

1. Shut down the Mac.
2. On the built-in keyboard, press and hold the Control (left side), Option (left side), and Shift (right side) keys for 7 seconds.
3. Without releasing those keys, press and hold the Power button as well.
4. Hold all four keys for another 7 seconds, then release them all.
5. Wait a few seconds, then press the Power button to turn on the Mac.

For Older Intel MacBooks (Non-Removable Battery, Pre-2018):

1. Shut down the Mac.
2. On the built-in keyboard, press and hold Shift, Control, and Option (all on the left side) along with the Power button.
3. Hold all four keys for 10 seconds.
4. Release all keys and turn on the Mac.

For Intel Desktop Macs (iMac, Mac mini, Mac Pro):

1. Shut down the Mac.
2. Unplug the power cord entirely from the wall or the back of the machine.
3. Wait exactly 15 seconds.
4. Plug the power cord back in.
5. Wait 5 seconds, then press the power button to turn it on.

Next Steps if Issues Persist

If you have successfully reset both the NVRAM and the SMC but your hardware issues persist, you are likely dealing with a physical component failure rather than a software misconfiguration. At this stage, your best course of action is to run Apple Diagnostics by holding the D key during startup (on Intel) or holding the power button to reach startup options and pressing Command + D (on Apple Silicon).