Single-diagram summary of how a modern Mac starts up in macOS 10.12 or 10.13, from pressing the Power button to running the kernel.
SMC
Important info about resetting the NVRAM with a firmware password, and new procedures for resetting the SMC in Macs with T2 chips.
What boot.efi does to prepare to load and run the kernel: building the hardware device tree, handling startup key commands, and more.
The Mac has completed its self-test routines, and now prepares to load the EFI firmware or ‘boot loader’. Where it finds it, what it needs, and how Secure Boot changes this.
What happens in your Mac when you press the Power button? Before it loads the EFI firmware, it goes through self-testing, and initialising key chips.
By default, your Mac’s cooling fans run at full blast. Only the control system slows them down when it is safe to do so. How to diagnose and fix its problems.
All about firmware, the SMC, NVRAM, and the new T2 chips which come in some models of Mac. When and how to reset, and more.
When should you reset your SMC and NVRAM, repair permissions, install a Combo update, or re-install the whole of macOS?
Effectively a Combo updater with the Supplemental Update, many apps are updated in a total payload of around 4.5 GB. And there’s the new emoji too.
As usual, Apple’s release notes for the Supplemental Update to High Sierra, released on 5 October 2017, fall […]
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