Questions tagged [nvram]
Non-volatile random access memory; RAM that doesn't lose the stored information when the power is turned off, unlike traditional RAM
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MacBook Pro 13 inch late 2013 disk startup error but after reset PRAM sometimes works normally
My MacBook Pro 13 inch late 2013 had battery issues, for long time I was only able to use on net adapter, and in the end not able to do anything at all. Because I used my work laptop I did not touched ...
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No Audio Output Source detected - Wired Headphones & internal speakers affected
Intel based MacBook Air (2017) is showing no audio sources in the output tab neither for the internal speakers nor for the connected headphone jack but audio over bluetooth seams to work fine.
Here's ...
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Keyboard and trackpad not working after logic board upgrade
I had an issue with RAM on my old logic board of a 2011 MacBook Air. I decided to replace the old logic board with a more recent i7 2017 logic board. I got to get all running but the keyboard and the ...
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How do I interpret the HW_BOOT_DATA field of nvram?
When I run nvram -x HW_BOOT_DATA the output in the data field appears to be a base64 encoded binary string. The length remains constant but some of the bits change between runs.
How do I interpret ...
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No signal on external monitor after sleeping or restarting. Consistently "fixed" by resetting NVRAM
I have a 2018 Mac Mini running macOS Monterey 12.6.
The Mac is connected to a single external monitor using HDMI.
Whenever the Mac wakes from sleep or is restarted normally, the monitor has no signal. ...
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How to use a specific keyboard layout upon boot?
I've installed DosDude's patches to get Catalina running on my Mac Pro 4,1.
However, I'm a Dvorak typist, and now I find I'm booting Catalina in "Canadian English" layout instead of Dvorak. ...
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How to disable M1 Mac auto-boot on lid open?
There have been answers that describe how this can be prevented for Intel Macs using an NVRAM setting, but this AutoBoot setting has no effect on an M1 Mac. There is a similar auto-boot setting in the ...
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Internet Recovery. Unlike Monterey, Sierra OS X Utilities starts with wi-fi connected, even after a nvram reset and a disk erase. How?
On boot, when I press Shift+Option+Command+r, a globe appears with a dropdown box to choose my ssid and password. After some time the Sierra Utilities starts and my wi-fi connection is enabled.
This ...
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Did unibody Macbook Pros have a backup battery (CMOS / PRAM)?
My mid-2009 13" unibody MacBook Pro died years ago. It's probably not worth fixing. I'm just curious if a dead CMOS/PRAM battery could have caused its demise?
iFixIt doesn't list any non-primary ...
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Make my Macbook "forget" a USB device (resetting NVRAM didn't help)
Tonight my 2019 MacBook Pro mysteriously stopped working correctly with my external (USB3) DVD drive. However, I know the drive is fine because my Windows machine and my old 2016 MacBook Pro can use ...
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Verbose Mode during startup not working on Apple Silicon
I have a Mac mini 2020 (with the Apple Silicon M1 chip).
I want it to boot up in verbose mode, i.e. the details of the boot process should be logged as text on the screen during bootup.
The following ...
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Does serverperfmode work on Apple Silicon Macs?
Is it possible to enable serverperfmode on an Apple Silicon Mac?
I am using an M1 Mac Mini on macOS 11.2, and following Apple's instructions. I enabled serverperfmode=1 in the NVRAM boot-args, and ...
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Find My Mac already in use (on a bought Mac) - how clear this option?
I bought a used Mac Mini (2018) from a (used Mac reseller), and today I've noticed that the previous owner is still signed in to Find My Mac (but it is me who is signed in to this Mac's iCloud).
...
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iMac 10,1 allegedly does not support nvram, and takes longer than usual to boot. What could be the issue?
Command+Option+P+R does nothing, and executing nvram -xp and nvram -c returns the same nvram is not supported on this system
This is on a clean install of Yosemite (installation of El Cap and above ...
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Why do I have to choose the language every time when I go into the recovery mode?
My MacBook Pro is 16 inch bought from 2019 and the macOS version is Big Sur. Last week, I reset the nvram then I found I have to choose language option every time I go into recover mode (by using ...
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Cannot set boot-args even with SIP disabled
I have installed macOS Big Sur as a guest system in Parallels Desktop 16. I disabled SIP. However, I'm still unable to change nvram values for boot-args. Is there another security feature that I haven'...
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Is there an equivalent to resetting NVRAM on an M1 mac?
I have an M1 Mac Mini that is exhibiting some strange issues that aren't going away after reinstalling macOS. I'd like to reset its NVRAM or whatever the nearest equivalent is for M1 macs, in case ...
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Does remapping modifier keys affect special boots?
I'm running Catalina 10.15.5. In the keyboard preferences there is the option to remap modifier keys, which I've done. My question is, do these remappings apply when using the remapped keys for ...
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Late 2011 MacBook Pro 13" stuck on white screen
My Mac model is MacBook Pro (13-inch, Late 2011) (MD314).
Things I've tried so far:
Reset NVRAM (PRAM) which actually does reset and laptop restarts when it resets.
Reset SMC.
Tried booting to ...
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How can I undo nvram recovery-boot-mode=unused if I don't know firmware password? [duplicate]
While trying to get into recovery mode, I used this:
sudo nvram recovery-boot-mode=unused
... hoping it'd take me directly to recovery mode. Instead, it prompts me for the firmware password. Which I ...
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Trying to Analyse a WIFI Hardware Problem
I have a MacBook Pro (13 ", Mid 2012) model running Mac OS 10.14.6 (Mojave). Of late I'm experiencing a lot of problems with the WIFI hardware frequently "shutting down" or going into a ...
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MacBook Pro 15-inches display not working: how to isolate the cause of the issue?
On last Saturday I left my MacBook Pro (15-inches display, mid-2012 release) on during the night in order to finish some backup tasks and I scheduled its shutdown for a certain time using shutdown -h. ...
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Black Screen on 13" Macbook Pro 2019/Catalina. Resetting NVRAM/PRAM, SMC does not work
My wife's Macbook Pro suddenly dropped to a black screen with the power still on; keys light up, caps lock light comes on; display is clearly getting power. Holding down the power button kills power ...
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NVRAM: Error clearing firmware variables: (iokit/common) not permitted
I cannot reset my NVRAM at startup (holding down ⌘ Command⌥ OptionPR does nothing), but I want to reset the NVRAM so I am trying to reset it with Terminal.
$ sudo nvram -c
nvram: Error clearing ...
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What is the command line equivalent of PRAM reset?
My wired keyboard is starting to flake out and I'm not able to PRAM reset the machine at boot with the Option ⌥ + Command ⌘ + P + R sequence. I tried plugging in a Windows keyboard and use Alt + ...
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Weird anomaly on my MacBook Pro
Recently I've encountered a problem, and quite frankly, of course it had to be one of those cases where nothing absolutely helps.
It started around a couple weeks ago, the system was getting random ...
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24" Intel iMac (2006) date and time keeps resetting on boot, even after new battery and NVRAM reset
Since a week my iMac, running Snow Leopard, behaves strangely in two ways:
First, I always unplug the iMac when I don't use it. Now, when I plug it in, it immediately starts, without me pressing the ...
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Conversion of a 2011 vintage Unibody Macbook Pro to Linux
I've got a Late 2011 17" MacBook Pro that got as far as High Sierra 10.13.6. My thought was to remove the SSD that's currently installed, replace it with another SSD, then install Linux Mint on this ...
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Macbook Pro mid-2012 restarts after entering password
Macbook Pro mid-2012 restarts after entering password and gives an error after restart
I'm unable to use any other boot command like Command + R etc as it leads to a screen with a lock and I've ...
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Macbook not turning on
My MacBook air 2015 was lid turned down for more than a month
When I opened the lid, it had 12% battery and I put it on charging and send an email to myself
After I came back it is blank and not ...
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Macbook Air (2013) trackpad not responding
The trackpad fails to respond after the computer got hung on a website video last night and then went into sleep mode. On wakeup I had to use the arrow keys to toggle through various apps and quit ...
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How to get write access to High Sierra (APFS) drive in Read-Only mode on Macbook with faulty AMD GPU
Some background: My 2011 17" MacBook Pro (running High Sierra) has finally succumbed to the Radeon issue and won't boot up. I know this because it would flicker green where there was pixel shading so ...
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Reset NVRAM, PRAM, and SMC, all in one go from the terminal?
I'd like to run some code, go away and have a coffee and come back to a MacBook with the NVRAM, PRAM and SMC all reset (rather than doing them manually with yoga postures to press all the keys, ...
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User account issues after resetting PRAM
So my 2012 iMac has been unusually cranky the past couple days and did not respond to the usual reboot I give when this happens, so I decided to reset the PRAM at the advice of many articles.
...
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How to enable Autoboot for old MacBook Air?
MacBooks released in and after 2016 have a feature that enables them to boot as soon as the lid is opened. I wanted to replicate the feature on my 2013 MacBook Air (MacOS Catalina Public Beta 5), so I ...
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NVRAM Showing Questionable Payload Variables... Can anyone verify if this is normal?
I used the terminal command in macOS 'nvram -xp':
student:~ admin$ nvram -xp
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www....
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MacBook Pro keep on "unplugging" battery and need SMC/PRAM reset
I recently brought my 2015 13" MacBook Pro to an Apple center to get a screen replacement for Staingate. They did it for free. Before this replacement my MacBook was doing really good actually.
After ...
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How to find out whether NVRAM was reset?
I was having some issues with my mac so I reset NVRAM by holding ⌘+⌥+P+R.
The problem is that this laptop does not chime when NVRAM is reset, so I'm not sure if NVRAM was indeed reset.
How can I ...
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Resetting PRAM through Terminal
For some reason, my Mac won't let me reset my PRAM in the usual way (by holding the relevant keys down when restarting), simply nothing happens when I try it and my Mac just boots up normally every ...
user206728
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Find My Stolen Mini Mac After Installing New Clean Mac OS X Installation
My Mac Mini was stolen from my office and I think it was stolen by my colleague. They are all software engineers and I think the thief will install a fresh version of macOS on the stolen Mac Mini.
My ...
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Disable Macbook internal display
I own a Macbook Pro 13 2017 (2 thunderbolt ports), and I would like to disable the internal display when an external monitor is connected to it through USB-C.
I have ruled out the following
Turn ...
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How is modifier key remapping implemented on Touchbar Macbooks?
How is modifier key remapping implemented on Touchbar Macbooks? Is it done by the main OS, or is it delegated to a controller associated with the keyboard itself?
I understand that the Touch Bar and ...
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How to reset NVRAM on iMac with bluetooth keyboard?
I have a problem with a swipe back in Safari. On my MacBook I could fix it by resetting of NVRAM. I can't find out how to do it on iMac with a Bluetooth keyboard. Do I really need a cable keyboard in ...
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Is there an equivalent of Linux's kernel memmap on OS X?
According to memtest86, there is a persistent single bit error in my MacBook Pro's 16GB of DDR RAM.
Since the error is in the second half of the physical address space, I can work around the problem ...
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How to enter various nvram boot-args
I'd like to set both vm_compression=1 plus serverperfmode=1. Can I achieve this by nvram boot-args "vm_compression=1","serverperfmode=1"
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What is stored in the NVRAM that could cause my Macbook Pro to fail to detect sound output devices?
My Macbook Pro (2016, 4 thunderbolt 3 ports) has this very annoying problem where something breaks in the audio system, and it stops playing sounds and being able to detect any output devices. It's ...
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Does resetting NVRAM reset EFI Boot Order?
I've had a Macbook Pro for a year or so now and have experimented with quite a few Linux distributions which have added and changed things in the EFI Boot Order. I am looking to clean things up. The ...
user244412
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Preferred Order of NVRAM/PRAM, SMC, and OS resets
Is there a preferred order in which I should reset the NVRAM/PRAM, SMC, and OS on my MBP?
If so, what is this order (and why)?
Edit: I intend to do all of them to completely reset my computer. No ...
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MacBook Pro 2012 15" can’t boot
When I turn it on, it shows the Apple logo and starts loading up to about 50%, then the screen turns black. Running the hardware test shows this:
Alert! Apple Hardware test has detected an error.
...
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Does NVRAM, PRAM or SMC have anything to do with the red light on a Riser lighting up but then not lighting up after a reseat and riser switch?
One of the red leds for dimm 3 raiser b lit up red on my MacPro early 2008 lit up, so I reseated the ram in question on it by switching it with it's counter part (swapped dimm 3 for dimm 4) and ...
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