The iMac EFI Update installer will update the EFI firmware on your iMac computer. When the iMac restarts, a gray screen will appear with a status bar to indicate the progress of the update.
It will take several minutes for the update to complete. Do not disturb or shut off the power on your iMac during this update.
Requirements:
· iMac
What's New in This Release: [ read full changelog ]
· This update improves the reliability of booting from the network, addresses an issue that can prevent HDCP authentication after a reboot, and resolves an issue with boot device selection when a USB storage device is hot-plugged.