iMac (Mid 2007) and later models: About startup tones
Summary
iMac (Mid 2007) and later model iMac computers, unlike other Macintosh computers, do not use the power LED to indicate there is an issue. iMac (Mid 2007) and later model iMac computers use tones instead.
Products Affected
iMac (21.5-inch, Late 2009), iMac (24-inch Mid 2007), iMac (20-inch, Mid 2009), iMac (20-inch, Early 2009), iMac (24-inch, Early 2009), iMac (20-inch, Mid 2007), iMac (27-inch, Mid 2011), iMac (27-inch, Late 2009), iMac (21.5-inch, Mid 2011), MacBook Pro (15-inch, Mid 2009), iMac (24-inch, Early 2008), iMac (20-inch, Early 2008)
The following table lists the new tones and their meaning:
One Moment Please
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