If you hear additional beeps or chimes at this point, this indicates a possible hardware issue and the startup sequence halts. It then performs a power-on self test (POST) and a BootROM test.

Your Mac initializes its BootROM and memory (RAM).

When you first turn on your Mac, the screen is black and you hear a startup sound if your Mac is from early 2016 and earlier. If you start from Windows using Boot Camp, your Mac doesn't display an Apple logo or the other screens in this article.The progress indicator can be a progress bar or a spinning indicator.The background at any stage of the startup process can be blue, black, or gray.You might see slight differences in startup screens or sequences mentioned in this article, depending on the model of your Mac, the version of macOS and firmware your Mac has, and which startup options you've selected. When you start your Mac from macOS, different screens appear to show you the startup progress, including any issues that might keep your Mac from starting up.

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