nedfromyes
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Q: imac 10.6.8 sleep problems

Hi,

 

Since the last update (possibly, not 100% sure) my iMac 2008 doesn't sleep any more, when I click on Apple->Sleep it pauses and then restarts - it is not a safe restart, it basically does a hard reset as if I've pushed the power button in for 10 seconds.

 

Any one had this?

iMac, Mac OS X (10.6.8)

Posted on Oct 26, 2012 3:28 PM

by John Galt,Solvedanswer
John Galt John Galt
Level 8 (49,330 points)
Mac OS X
A:

Power or other problems related to unexpected system sleep, shutdown, lights or fans call for an SMC reset:

 

Resetting the System Management Controller (SMC)

 

Resetting the SMC for Mac Pro, Intel-based iMac, Intel-based Mac mini, or Intel-based Xserve

 

  1. Shut down the computer.
  2. Unplug the computer's power cord.
  3. Wait fifteen seconds.
  4. Attach the computer's power cord.
  5. Wait five seconds, then press the power button to turn on the computer.

Posted on Oct 26, 2012 3:30 PM

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nedfromyes

Q: imac 10.6.8 sleep problems

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  • Helpful answers

  • by John Galt,Solvedanswer

    John Galt John Galt Oct 26, 2012 3:30 PM in response to nedfromyes
    Level 8 (49,330 points)
    Mac OS X
    Oct 26, 2012 3:30 PM in response to nedfromyes

    Power or other problems related to unexpected system sleep, shutdown, lights or fans call for an SMC reset:

     

    Resetting the System Management Controller (SMC)

     

    Resetting the SMC for Mac Pro, Intel-based iMac, Intel-based Mac mini, or Intel-based Xserve

     

    1. Shut down the computer.
    2. Unplug the computer's power cord.
    3. Wait fifteen seconds.
    4. Attach the computer's power cord.
    5. Wait five seconds, then press the power button to turn on the computer.

  • by nedfromyes,

    nedfromyes nedfromyes Oct 26, 2012 3:39 PM in response to John Galt
    Level 1 (0 points)
    Oct 26, 2012 3:39 PM in response to John Galt

    Thanks for the quick reply - I put me iMac to sleep (which reset when it powered back up, not on sleep) logged in and see a reply before I've had a chance to edit my question!

     

    Ok, I'll try a SMC reset. Just to clarify - it does in fact sleep ok, with the sleeping led strobing gently, but on waking up it bongs and reboots.

     

    I'll edit this post if it works or doesn't in 5 mins.

  • by nedfromyes,Helpful

    nedfromyes nedfromyes Oct 26, 2012 4:17 PM in response to nedfromyes
    Level 1 (0 points)
    Oct 26, 2012 4:17 PM in response to nedfromyes

    Thanks John, that didn't solve it BUT it did help - while unplugging the power I unplugged the external powered usb hub which allowed the sleep to work properly.

     

    Unplugging everything one at a time eventually led me to the external dvd writer, which is powered by 2 usb ports. Well, it turns out that my usb hub was no longer powered, so on waking up from sleep mode I'm guessing (much) more than 500ma of power was being drawn from the one iMac usb port, causing the problem.

  • by John Galt,

    John Galt John Galt Oct 26, 2012 5:42 PM in response to nedfromyes
    Level 8 (49,330 points)
    Mac OS X
    Oct 26, 2012 5:42 PM in response to nedfromyes

    That would certainly explain it.