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

Filter by
Sorted by
Tagged with
1
vote
1answer
50 views

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 ...
2
votes
0answers
95 views

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 ...
3
votes
1answer
469 views

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 ...
1
vote
0answers
58 views

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 ...
0
votes
0answers
817 views

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). ...
1
vote
0answers
152 views

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 ...
0
votes
0answers
29 views

Decode kernel crashes from nvram

When I'm sorting my files today, I found a dump of nvram -p some time ago that contains a kernel crash log. I tried to decode it using url decode, but it just produced unrecognizable data. How can I ...
0
votes
0answers
82 views

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 ...
0
votes
0answers
423 views

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'...
6
votes
2answers
10k views

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 ...
1
vote
1answer
21 views

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 ...
1
vote
0answers
107 views

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 ...
1
vote
1answer
212 views

How can I undo nvram recovery-boot-mode=unused if I don't know firmware password?

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 ...
3
votes
3answers
66 views

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 ...
0
votes
0answers
23 views

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. ...
0
votes
1answer
174 views

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 ...
4
votes
1answer
11k views

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 ...
0
votes
0answers
139 views

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 + ...
0
votes
0answers
31 views

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 ...
0
votes
1answer
44 views

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 ...
1
vote
1answer
206 views

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 ...
0
votes
1answer
66 views

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 ...
0
votes
1answer
28 views

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 ...
2
votes
1answer
87 views

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 ...
0
votes
2answers
2k views

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 ...
3
votes
1answer
10k views

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, ...
0
votes
0answers
46 views

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. ...
2
votes
1answer
789 views

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 ...
0
votes
1answer
516 views

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....
1
vote
1answer
381 views

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 ...
5
votes
2answers
9k views

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 ...
2
votes
2answers
16k views

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 ...
2
votes
1answer
338 views

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 ...
3
votes
1answer
892 views

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 ...
1
vote
0answers
195 views

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 ...
2
votes
1answer
4k views

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 ...
2
votes
1answer
163 views

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 ...
1
vote
2answers
718 views

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"
1
vote
0answers
112 views

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 ...
1
vote
1answer
740 views

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 ...
1
vote
1answer
193 views

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 ...
2
votes
1answer
370 views

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. ...
1
vote
1answer
128 views

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 ...
0
votes
1answer
1k views

nvram command not found

When attempting to check the change the contents of the nvram (adding bootup chime, etc.), I am continually returned with the error: nvram: command not found. This occurs even when I attempt to just ...
0
votes
1answer
165 views

Fix the constant shift issue [duplicate]

On my Macbook Air A1466 the shift key seems to be constantly pressed, even during boot so it only boots into safe mode because of this. The issue exists both before and after replacing the keyboard ...
1
vote
0answers
304 views

Macbook turns off before battery is 0% when left unplugged. (Already reset SMC and PRAM several times) [duplicate]

This is my first question on this forum. My MacBook has been turning off randomly when left unplugged. It shuts down before the battery indicator reaches 0%. I have reset the SMC and PRAM several ...
0
votes
1answer
3k views

Macbook Pro screen keeps randomly going black after login, weird issues

A couple days ago while I was using my 15 inch Macbook Pro 2015 Retina Display laptop (got it brand new 2-3 months ago, running latest version of Sierra), the screen flashed black a few times, and ...
2
votes
2answers
20k views

Setting a NVRAM variable in normal boot not permitted but allowed in recovery mode

If memory serves me right then in Yosemite it was possible to set the NVRAM variable agc with nvram boot-args even in normal full boot mode. This seems to have changed in later versions of the OS. ...
1
vote
0answers
654 views

MacBook Pro stuck on gray boot screen

This morning, my mom logged into her computer as normal, used Mail to check her email, and then got distressed when seeing "squiggles and lines" on her monitor. When trying to restart her machine, it ...
1
vote
1answer
519 views

White Screen – nothing works after NVRAM reset

I can't boot my iMac (27", late 2012) and only get to see the white screen. Nothing works, CMD+R, CMD+ALT+Shift+R, Shift, C, CMD+S, ALT … I can hear the startup chime, screen goes white and stays ...