Macs are nice computers, but they’re not without their issues that can spur up at random times. Fortunately, troubleshooting problems on a Mac isn’t incredibly difficult and there are tons of simple steps you can take as a Mac user before calling AppleCare for support.
One of the easiest troubleshooting steps is resetting your Mac’s NVRAM, a step which can solve an array of problems. In this tutorial, we’ll explain what the NVRAM is responsible for and how to reset it to fix common problems.
What is NVRAM?
Your Mac’s NVRAM (non-volatile random access memory) is a type of non-volatile memory, which means that even when power is no longer being supplied to it, it can retain its memory contents. This is different from volatile memory, which loses all of its memory contents whenever the power supply is cut off from it.
As noted by an Apple support document, the NVRAM is present on all Intel-based Macs and is responsible for storing information related to a variety of software functions on your Mac that are essential to the user experience in the OS X operating system; this variety includes the following:
- The volume at which you’ve set your speakers
- The resolution your display has been configured at
- The start-up disk you’ve chosen to boot up with by default
- The time zone you’ve selected for your Mac to display the time for
- Any recent information logged by a kernel panic
This information has to be stored in non-volatile memory because if the memory were unable to retain information about your system volume, display, time zone, and start-up disk each and every time you turn off your Mac, then your Mac would restart with a default setting for each of the aforementioned system settings all the time, rather than remembering the settings you’ve chosen for each.
Why to reset the NVRAM on your Mac
If you are experiencing any issues with your system’s speaker volume, screen resolution, system time, or start-up disk, and there doesn’t appear to be any simple way of fixing the issues from OS X, you may be due for resetting the NVRAM, as it’s possible it’s not doing its job properly due to memory corruption.
Resetting the NVRAM will put your system’s NVRAM back to factory defaults, which means when you restart your computer after resetting the NVRAM, your system volume, screen resolution, and start-up disk selection settings will all be set to how they were configured when you turned your Mac on for the first time after removing it from its factory packaging.
How to reset your Mac’s NVRAM
Resetting your Mac’s NVRAM is a simple process, it just involves restarting your Mac and holding down a certain keyboard key sequence as it boots back up. We’ll walk you through the steps below:
Step 1: Completely shut down your Mac by using the “Apple” menu in the Menu Bar and selecting the “Shut Down” option.
Step 2: After shutting down your Mac, locate the Command (⌘), Option, P, and R keys on your keyboard, as these are the keys you’ll be using.
Step 3: Turn on your Mac using the power button.
Step 4: Press and hold the Command (⌘), Option, P, and R keys on your keyboard at the same time as soon as you hear your Mac’s startup chime sound.
Step 5: Continue holding these keys until you hear the startup sound for a second time, then release the keys all at the same time.
Note: The volume level of the second startup chime may be different from the initial startup chime. This is a good sign, as it indicates your system volume level has been reset to factory settings and indicates a successful NVRAM reset.
Step 6: When your computer restarts, re-configure any volume settings, screen resolution settings, time zone settings, and start-up disk settings as needed.
Once you’ve completed all these steps, you’re finished, and your Mac should stop behaving oddly. If it doesn’t you may need to contact AppleCare for further assistance, as it’s possible the logic board itself could be bad. Apple notes that there is a small battery on the logic board that helps the NVRAM retain information that can go bad after time, and sometimes the battery is the only thing that needs to be replaced.
Older non-Intel Macs use PRAM or parameter random access memory instead of NVRAM. The reset process for PRAM is exactly the same on these Macs as the reset process for NVRAM on modern Macs.
Hopefully resetting the NVRAM is all you’ll ever have to do to fix small issues with your Mac, but if you ever need to try other troubleshooting steps, we’ve got all the guides you’ll ever need.
- How to reset your Mac’s system management controller (SMC)
- How to fix common Bluetooth problems on your Mac
- Fixing sound issues when using an HDMI TV and computer speaker setup with your Mac
- How to fix slow or jittery mouse movements on your Mac
Did resetting your Mac’s NVRAM help you any? Share in the comments!