Reset SMU
Posted on 25 April 2006 in Apple Hardware, Macintosh Tips & Help, iMac | No Comments »
Resetting the SMU can resolve some computer issues such as not starting up, not displaying video, sleep issues, fan noise issues, and so on. If your computer still exhibits these types of issues even after you’ve restarted the computer, try resetting the SMU. To reset the SMU on one of these iMacs:
- Turn off the computer by choosing Shut Down from the Apple menu, or by holding the power button until the computer turns off.
- Unplug all cables from the computer, including the power cord.
- Wait 10 seconds.
- Plug in the power cord while simultaneously pressing and holding the power button on the back of the computer.
- Let go of the power button.
- Press the power button once more to start up your iMac.


