iMac beeps 3 times repeatedly when trying to boot up from a Mac OS X install DVD I have another issue with my iMac, the issue is that it beeps 3 times and they repeat when I start up from a Mac OS X install disc. Recently, I inserted a Mac OS X install disc into my computer, and used the Startup Manager to select the install disc and start/boot up from it. After a while at the grey Apple logo screen, the Mac played 3 tones, and then after 5 seconds, the tones played again/repeated, indicating a POSSIBLE hardware issue, and the startup procedure halted. Do you know what three tones, then a five second pause mean on a Mac? Might be an issue with the RAM. Do any of YOU know?
3 tones indicate a RAM failure, my recommendation is to remove all the RAM sticks and verify one by one; to identify which one is damaged.
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About Mac startup tones