NVRAM (nonvolatile random-access memory) is a small amount of memory that your Mac uses to store certain settings and access them quickly. PRAM (Parameter RAM) stores similar information, and the steps for resetting NVRAM and PRAM are the same.
This video will show you how to Fix your MacBook by resetting SMC System Management Controller. This process can fix many issues with your MacBook. I have a MAC PRO 3,1 8-Core that all USB ports stopped working, I tried the SMC reset, and it does not work, PRAM and NVRAM reset dont work since the USB ports don't work, I dont have a wireless keyboard or mouse (bluetooth), and even if I had I cant configure them since I cannot use the mouse or Keyboard. So basically stuck. Yet another component of your Mac’s hardware that stores crucial settings is the System Management Controller (SMC), a circuit that deals with power management, temperature.
Settings that can be stored in NVRAM include sound volume, display resolution, startup-disk selection, time zone, and recent kernel panic information. The settings stored in NVRAM depend on your Mac and the devices that you're using with your Mac.
If you experience issues related to these settings or others, resetting NVRAM might help. For example, if your Mac starts up from a disk other than the one selected in Startup Disk preferences, or a question mark icon briefly appears before your Mac starts up, you might need to reset NVRAM.
How to reset NVRAM
Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. You can release the keys after about 20 seconds, during which your Mac might appear to restart.
- On Mac computers that play a startup sound, you can release the keys after the second startup sound.
- On Mac computers that have the Apple T2 Security Chip, you can release the keys after the Apple logo appears and disappears for the second time.
If your Mac is using a firmware password, this key combination does nothing or causes your Mac to start up from macOS Recovery. To reset NVRAM, first turn off the firmware password.
When your Mac finishes starting up, you might want to open System Preferences and adjust any settings that were reset, such as sound volume, display resolution, startup disk selection, or time zone.
Learn more
- If you're using a desktop Mac instead of a notebook, and settings such as sound volume or time zone are reset every time you shut down and unplug your Mac, you might need to replace the battery inside your Mac. This small battery is on your computer's logic board, and it helps NVRAM retain settings when your Mac is unplugged. You can take your Mac to an Apple service provider to replace the battery.
- If you experience issues with sleep, wake, power, charging your Mac notebook battery, or other power-related symptoms, you might need to reset the SMC (System Management Controller).
How to reset your SMC on any Mac?
You may have noticed reduced Apple computer functionality, tried several methods to reset your Mac, but are still unable to find a solution. Furthermore, if you are not an experienced IT user, you may not be aware of components such as SMC (System Management Controller) and others.
System Management Controller is a low-level Mac hardware component that controls computer power consumption, battery charging and functionality, thermal and fan activity, GPU and video mode functionality/video output, sleep/wake modes and led lightning management, and other hardware functionality. Resetting the SMC might solve issues related to these devices. In this article, we describe common issues and ways to reset the System Management Controller for the most popular Apple products.
Table of Contents:
It is recommended to run a free scan with Malwarebytes - a tool to detect malware and fix computer errors. You will need to purchase the full version to remove infections and eliminate computer errors. Free trial available.
The most popular issues related to SMC
Resetting the SMC will not return your computer to new, but it is a useful tool to solve many hardware problems.
A list of the most common problems that SMC reset might solve:
- Problems with Mac cooling fans and fan management. For example, fans running at high speed despite normal CPU usage and temperature, or fans not working at all. In the last case, if a reset does not solve the issue, check that the fan is not impeded.
- Power management and battery life problems. For example, the Mac does not power up, does not transition to 'wake' mode from 'sleep', unwanted revert to 'sleep', or portable Mac not responding to lid opening and closing.
- Lightning issues. For example, battery indicator lights not working, unable to manage display or keyboard back lights, or lights not working at all.
- Video and external displays do not work properly. For example, video mode and external display not working correctly, or at all.
- General performance and functionality problems. For example, poor computer performance and responsiveness (perhaps caused by partial CPU or hard disk usage), external ports with Airport and Bluetooth do not work, cannot detect or mount external devices or drives.
If you experience one or more of these problems, perform an SMC reset by following the instructions below for most Apple models.
Reset SMC of a MacBook Air, MacBook Pro Retina, or MacBook Pro with an integrated battery
Before you proceed, bear in mind that, by resetting the SMC, you are erasing all data such as power settings, sleep schedule, and other customizations. All settings will revert to their defaults.
The path to reset SMC on most Apple laptops, which have none-removable battery:
First, shut down the device and connect the power adapter to the Mac. Hold down the Shift, Control and Option keys while clicking the power button. Finally, release all keys simultaneously - the light on MagSafe adapter may change color to signify that SMC has been reset. After a successful reset, reboot your computer in the usual way.
Reset your SMC on iMac, Mac Pro, Mac Mini
Note that performing an SMC reset for a non-portable Apple device is different for portable devices. As with MacBooks and portable devices, however, the procedure is straightforward and any problems with SMC on a desktop Mac will be similar to those of a laptop.
To reset SMC on a non-portable device, follow these instructions:
- Shut down the Mac.
- Disconnect the power cord.
- Hold down the Mac power button for five seconds.
- Release the button, reattach the power cable, and boot the Mac in the usual way.
Reset SMC of a MacBook or MacBook Pro's with removable battery
Some earlier Apple laptops had detachable batteries, so the SMC reset is performed in a slightly different way to newer models.
To perform an SMC reset follow these instructions:
Reset Smc Mac Pro 2008
Shutdown the MacBook or MacBook Pro and remove the battery. Disconnect the power adapter, hold the power key for 10 seconds. Release the button and reattach your power adapter and battery. Turn on the Mac in the usual way.
Alternative method for Mac Pro manufactured in 2012 or earlier
If you own a Mac Pro produced in 2012 or before, and the normal reset (described earlier) did not work, try a manual SMC reset: press the reset button located on the Mac Pro motherboard.
Now, follow these instructions to manually reset the SMC:
How To Reset Smc On Macbook Air
- Shut down the Mac.
- Unplug the Mac power cord.
- Open the Mac Pro side access panel.
- Below the Drive 4 sled and adjacent to the top PCI-e slot, you should find a small button labeled SMC. Press and hold down this button for 10 seconds.
- After resetting, close the Mac Pro side access panel, reconnect the Mac power cord, wait for at least five seconds, and then turn the computer back on by pressing the power button.
Reset Smc Macbook Pro 2012
After the Mac SMC has been reset, hardware issues should be resolved. If you continue to experience the same problems, there might be more serious, or different, issue that need to be troubleshooted separately.