Target Display mode may not work after waking from sleep

Products Affected

iMac (27-inch, Late 2009)

Symptoms

Sometimes after waking a portable computer from sleep that is connected by a Mini DisplayPort to Mini DisplayPort cable to an iMac (27-inch, Late 2009) in Target Display Mode, the image from the iMac appears on the iMac screen instead of the image from the portable.

Resolution

Download and install the 27-inch iMac SMC Firmware Update 1.0 to address this issue.

Additional Information

Learn more about using a 27-inch iMac as an external display, also known as Target Display mode.

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