Intel-based Mac: Startup sequence and error codes, symbols
The following is an overview of the startup sequence, error conditions, and behaviors for all Intel-based Macintosh systems.
Note that some newer Macintosh models only use tones to indicate error conditions. See this article for more information.
||Boot-ROM/RAM check is initialized
- Black screen, power LED on - POST or BootROM failure
- Flashing power LED once per second - bad RAM, no RAM
- Three flashes, a pause, and three more flashes (occurs continuously) - marginal RAM
- Metallic Apple - found boot.efi
- Circle with Slash - could not load boot.efi, or some other issue
- Flashing globe - looking for booter/kernel on netboot server
- Metallic Apple with spinning earth below - found booter/kernel on netboot server
- Broken Folder that blinks - no bootable device has been found
||Grey screen with Metallic Apple and spinning gear
||Login window appears
|User Environment Setup
||The text "Logging in..." appears in login window along with a progress bar. Upon successful login, the Desktop and Dock appear.
Learn more about trouble shooting on Mac OS X's startup process.