iMac EFI Firmware Update 1.1
This EFI Firmware Update fixes several Boot Camp, start up, and wake-from-sleep issues on iMac computers.
After the firmware update is successfully applied to your computer, your Boot ROM Version will be:
IM41.0055.B08 (early 2006)
IM42.0071.B03 (17-inch mid 2006)
IM52.0090.B03 (17-inch late 2006 CD)
IM51.0090.B03 (20-inch late 2006)
You can confirm the version of the Boot ROM installed on your computer using System Profiler.
Note: Print or write down these instructions before you begin the update.
To update the firmware on your Intel-based iMac:
- Quit all other open applications.
- Click Shut Down in the iMac EFI Firmware Update window and wait for your computer to shut down.
- Press and hold the power button on your iMac until the power indicator light flashes repeatedly, then release the power button to begin the update.
A status bar indicates the progress of the update.
Important: Do not interrupt the update.
Your computer restarts automatically when the update is completed and opens the iMac EFI Firmware Update.
- Click OK, if the firmware is now up-to-date.
If these instructions appear on your screen again, the firmware update was not successful. Repeat steps 2, 3 and 4.
For more information, please visit this website: About firmware updates for Intel-based Macs.