How to reset PRAM/NVRAM and SMC on Mac

Most Mac users are familiar with the concept of RAM, or random access memory, and many are probably much too used to running out of it. Very often, RAM usage relies on the functioning of PRAM/NVRAM. So when your Mac runs super slow, it might have to do with PRAM/NVRAM. Another hardware component of Mac that controls battery, fans, and more — the SMC — can also be a source of Mac misbehavior.  

This article looks at some of the common problems that result from SMC or PRAM/NVRAM malfunctions, as well as how to reset them to solve those problems.

What is PRAM/NVRAM and SMC?

PRAM stands for parameter random access memory and is part of older PowerPC models, while Intel Macs have NVRAM (non-volatile random access memory). Both are responsible for holding information about how a Mac is configured, including date/time, mouse, volume, and various other things. They are powered by a battery independent of the Mac itself, so their information is retained even when the machine is switched off. 

SMC stands for System Management Controller, the full name of which offers up a nice analogy for non-technical folks looking to understand what an SMC does. Like an air traffic controller or a train controller, the SMC is responsible for controlling a number of Mac’s functions:

• Detecting (and responding to) the opening/closing of a laptop lid
• Analyzing a power button being pressed to determine if it should respond by putting the Mac to sleep or shutting it down completely
• Managing battery performance and displaying remaining battery life
• Adjusting fan speed to control the temperature of a Mac
• Controlling backlighting and detecting ambient light to set appropriate levels. 

When any of these things go wrong, it can be hugely frustrating. That’s true not only because it can make using your Mac much more difficult, or even impossible, but because the issues it puts out are so random it can make you feel like you’re being haunted!

When should you reset PRAM/NVRAM and SMC on your Mac? 

First things first, we need to pinpoint whether a PRAM/NVRAM issue or an SMC problem (or neither, for that matter) is what’s causing all the trouble. Without knowing that, there’s no way to find out whether a PRAM reset or SMC reset on MacBook Pro, iMac Pro, or Mac Pro will help. 

Let’s start with some of the problems commonly associated with SMC issues as, until you realize what’s going on, they can be some of the most frightening for a typical Mac user:

• Your Mac doesn’t turn on when you open it
• The trackpad doesn’t work
• You can’t connect to WiFi
• The lights or backlights on your Mac are behaving erratically
• Your fan is running extremely high, even during non-intensive processes
• Your computer runs or shuts down slowly. 

Meanwhile, PRAM/NVRAM problems might cause issues like:

• Incorrect date or time being displayed
• Keyboard doesn’t respond as it should
• Volume doesn’t work correctly
• Erratic scrolling and mouse-clicking behavior
• Problems with AirPort
• Sudden and unexplained shutdowns or problems setting the correct boot volume. 

That’s a hefty list of potential problems and, while encountering any one of them on their own is unpleasant, your Mac exhibiting multiple items from the list is downright frustrating. But before delving into how to reset PRAM/NVRAM or SMC, it’s wise to take a few steps to isolate other potential causes of these issues.

Before you reset  

Run a scan with CleanMyMac X. This tool lets you perform quick and easy scans to see if there’s anything wrong with your hard drives, check for malware, purge cluttered caches, and more. All you need to kick things off is a single click of the Scan button, although you can also manually delve into individual issues if you prefer. After using CleanMyMac X, you might get your issue fixed without having to reset PRAM/NVRAM or SMC! 

How to reset the SMC on a Mac 

If you think you need to reset the SMC, we’ll guide you through the whole process. Make sure you read the instructions that apply to your Mac model because they are completely different!  

Reset SMC on an M1 Mac 

Good news for the users of Apple Silicon Macs: you don’t have to lift a finger to reset the SMC on your Mac. That’s because these new Mac models don’t have the system management controller any longer. So sit back, run a quick CleanMyMac X scan, and relax. 

iStat Menus will help you keep things under control if you continue having the performance issues. Simply click the icon in your menu bar to view and manage fans, battery, CPU, etc. 

Reset SMC on an Intel Mac 

Have an Intel Mac? Then this guide is for you. There are various ways to complete a Mac reset SMC, depending on the Intel Mac model you have. As SMC reset on MacBook Pros with a removable battery is the easiest, let’s begin there:

1. Shut down your Mac
2. Remove the battery
3. Press the power button and hold it for five seconds
4. Reconnect the battery and turn on your Mac. 

No removable battery? The process will be a bit different:

1. Shut down your Mac
2. Press Shift + Control + Option on the left side of your keyboard, then the power button or Touch ID, and hold them all for 10 seconds
3. Release the keys and turn on your Mac. 

If your MacBook has a T2 Security Chip (i.e. it’s a model from 2018 or later), the process looks different yet again:

1. Shut down your Mac
2. Press the power button and hold it for 10 seconds, then restart
3. If that doesn’t help, press the right Shift key + left Control key + left Option key, then hold them for seven seconds
4. Release all keys and turn on your Mac. 

That lack of consistency (five seconds, seven seconds, 10 seconds, right Shift, left Shift) might seem a bit infuriating when you read all of the different methods together, but it’s not so bad once you’ve determined the MacBook model you have and the steps you need to take.

Tip: Resetting the SMC didn’t help? Try taming your resource-hungry apps with App Tamer. Our experience with this app proves that it can significantly improve a Mac’s speed, reduce CPU usage, and fix common performance issues. 

Resetting SMC on older Mac devices (pre-2018)

With older desktop Macs, you have to take a different route. The route will vary depending on the age of your Mac. For older pre-2018 Macs the process is very simple:

1. Shut down your Mac
2. Unplug your power lead and wait 15 seconds
3. Reconnect your power lead and wait another five seconds
4. Turn on your Mac. 

Reset SMC on Mac Mini, iMac, or Mac Pro

For newer Macs with a T2 Security Chip (e.g. an iMac Pro), you’ll need to take the following steps for the SMC reset:

1. Shut down your Mac
2. Press the power button and hold it for 10 seconds
3. Release the power button and restart your Mac
4. If that hasn’t resolved the issue, shut down your Mac again 
5. Unplug your power lead and wait 15 seconds
6. Reconnect your power lead and wait another five seconds
7. Turn on your Mac. 

Congratulations: you now know how to reset SMC on Mac!

Resetting PRAM/NVRAM on Mac

Note: We’re not discussing PRAM/NVRAM reset for Apple Silicon Macs because it doesn’t apply to them. The process that is similar to resetting NVRAM will run automatically as you start up your Mac, whenever there’s such a need. 

PRAM/NVRAM reset is a bit easier to do than resetting SMC. If you’re not sure whether you have PRAM or NVRAM, there’s no need to check manuals or google “what is a PRAM?” to find out. Regardless of which one your Mac uses, the process to reset PRAM on Mac or perform a NVRAM reset is exactly the same:

1. Shut down your Mac and disconnect all USB devices (except wired keyboards)
2. Press the power button and hold down Command + Option + P + R immediately after doing so
3. Hold those keys until your Mac restarts and you hear a second startup chime or, for Macs with a T2 Security Chip, until the Apple logo appears and disappears a second time
4. Check the Startup Disk, Date/Time, and Display sections of System Preferences to ensure that everything looks the way you want it

That’s all there is to it. You may notice that some of your preferences relating to keyboard layout, mouse tracking, time, and volume have been lost, so you might like to make a note (mental or otherwise) of these if you’re very particular about them.

Optimize your Mac without resetting PRAM/NVRAM or SMC

Issues caused by PRAM/NVRAM or SMC can be pretty scary when you don’t know what’s causing them, but once you figure out what the culprit is, they are not too difficult to deal with. 

Using software like CleanMyMac X and iStat Menus, mentioned above, to monitor the health of your Mac can be helpful for eliminating possible causes. Additionally, we recommend that you install App Tamer to reduce CPU usage and take complete control of the processes running on your Mac. 

iStat Menus, CleanMyMac X, and App Tamer are available for a free trial through Setapp, a platform of more than 230 Mac and iPhone apps and utilities that can solve even the most difficult technical challenges.