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Is your Mac acting strange? Here’s how to reset the PRAM and SMC to clear up quirks

Is your Mac acting weird or crashing lately? Are the indicators and lights malfunctioning? Does it refuse to charge properly, even with a new battery? Is the operating system acting too slow? Are you having problems with multiple types of connections? The answer to these problems could be an issue with your PRAM or SMC. These are parts of your Mac that typically work silently in the background to make sure that all settings — especially hardware-oriented settings — function as designed.

More: Kickstart your sluggish Mac with these 11 tips and tricks

However, sometimes these settings can get confused or tied in knots due to a variety of causes. When this happens, you can often put things right by resetting these parts on your Mac. Below, we’ll show you exactly how it’s done.

Note: Resetting these parts on your Mac is usually safe, but that’s not a guarantee. Make sure you try basic rebooting and other troubleshooting first, and back up your data before you begin. This will also reset any customized settings that you may have, so you may have a little work to do once you start back up.

Resetting PRAM/NVRAM

PRAM/NVRAM control the basic settings that allow MacOS to be… well, MacOS. This includes startup fonts, how long it takes to click things, mouse speed, speaker volumes, port configuration, and a host of other operating facets. These can often be adjusted via the settings menu or by other means, but PRAM can also be reset entirely to help fix problems that have developed.

Oh, and about that name: This memory was once called PRAM (parameter RAM), but is now technically NVRAM (non-volatile RAM), and because acronyms tend to stick around, the terms are somewhat interchangeable.

Step 1: Shut down your Mac as you normally would.

Step 2: Start your Mac up again, but the moment you hear the startup chime, hold down the Command, Option, P, and R keys at the same time.

Step 3: Keep pressing the keys until you hear a second chime and your computer restarts. This is the sign that the PRAM has been rebooted — you can let up on the keys now.

Step 4: Log back in and check to see if the problems that were plaguing you before still persist. If they’re gone, then rebooting your PRAM/NVRAM worked. Keep in mind, however, that this doesn’t always work. Instead, you may get a gray screen that just sticks around, like your Mac isn’t sure what to do while you’re pressing the keys. This can happen due to a problem with your keyboard, and other attached devices. Unplug all other accessories, make sure your keyboard doesn’t need new batteries, and try again.

Resetting SMC

SMC (system management controller) isn’t data, but rather a piece of hardware that manages important physical aspects of your Mac — i.e., power settings, temperature sensors, LED indicators. If you’re having problems with settings and other hardware issues, the SMC may be malfunctioning, especially if you tried tweaking some of your hardware in the past. This can be particularly dangerous because a glitching SMC can cause overheating and various power issues. Fortunately, you can reset your SMC to its original factory settings, which can fix serious problems such as these. However, the process for doing so is differs based on whether you’re using a desktop Mac or a Macbook.

Desktop Macs

Step 1: Shut down your Mac as you normally would. Afterward, unplug the power cord from the wall.

Step 2: Wait for at least 15 seconds.

Step 3: Plug the power cord back in, wait a few more seconds, and then turn your Mac back on. That’s it! The SMC should reboot and hopefully fix your problem.


Step 1: Check to see if the battery is removable, as newer Macs don’t have removable batteries and the steps differ. We’ll divide Step 2 into two parts for the different types of MacBooks.

Step 2 (for Macbooks with removable batteries): Take out the battery and unplug your Mac. It may look dead, but you can still reset the SMC. Just press the power button, and count to five before letting go. Now, put the battery back in and start your machine as you would normally.

Step 2 (for Macbooks without removable batteries): Plug your Macbook into a power source and turn your Mac off. Once off, press and hold the Shift, Option, Control, and Power buttons simultaneously. Hold them for about a second, and then release. Wait several seconds, and then press the power button again to turn your Mac on.