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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

2
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1answer
234 views

Yosemite turns on “reduce transparency” at every login or wake after battery failure

Recently, I was using my rMBP on battery power, with about 20%-30% remaining battery, according to the battery indicator. It suddenly shut off, and would not power on (not even showing the "battery ...
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0answers
306 views

Does system integrity protection prevent nvram(8) from setting -x as a boot argument for safe mode?

When pre-release macOS Sierra is in safe mode with -x as a boot argument in NVRAM, the following command works as expected: sudo nvram boot-args="-v" When Sierra is booted in normal mode, the ...
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0answers
36 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 ...
1
vote
0answers
34 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
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0answers
603 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
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0answers
259 views

saving / restoring the NVRAM

I need to find a reliable way to save and restore the contents of NVRAM. Would this be correct? Preservation nvram -x -p > ~/nvram.xml Recovery: sudo nvram -x -f ~/nvram.xml