My Mac keeps restarting itself part way through bootup

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Level 1

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My Mac keeps restarting itself part way through bootup

My Mac keeps restarting itself part way through bootup. Have tried safe mode, recovery mode and Cmd-option-P-R. but it keeps happening and I can get no further

Posted on Aug 31, 2019 5:33 AM

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Answer 1

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sachalew Author

Level 1

4 points

Sep 1, 2019 5:31 AM in response to HWTech

yes to both the above. Also recovery and safe mode methods. whatever I try I just get the startup chime, the screen goes white and displays the apple logo with the progress bar below.

Soon as the progress is about 3/4 across the screen goes black, silent, and then starts all over again with apple logo and progress bar, this continues ad nauseam until I hard restart and fail another way.

Help

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Answer 2

HWTech

Level 9

62,474 points

Sep 1, 2019 9:22 AM in response to sachalew

Thanks for clarifying the details. Can you boot into Single User Mode using Command + S?

What is the exact model of the computer? You can get this information by entering your serial number here. What version of macOS is on the boot drive? I missed the fact earlier that you have a white screen on boot which indicates an older model computer.

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