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Fan Always On

Discussion in 'OS X Mountain Lion (10.8)' started by Mykonos, Mar 20, 2012.

  1. macrumors member

    After installing the Developer Preview 2, I fired up the updated Notes application. Suddenly my fan won't shut up. Anyone know how I can address this issue? I've tried to unsync Notes, resync, to no avail.
  2. macrumors demi-god


    • Your fans are always on, spinning at a minimum of 2000 rpm (on MBPs... you didn't mention what Mac model you have).
    • Install iStat Pro to get accurate readings of your fan speeds and temps, among other things.
    • If your fans are spinning faster without increased heat, try resetting the SMC.
    • If you do have increased heat, launch Activity Monitor and change "My Processes" at the top to "All Processes", then click on the CPU column heading once or twice, so the arrow points downward (highest values on top). Then look to see what may be consuming system resources.
  3. macrumors member

    Yeah sorry about that! I have a late 2011 MacBook Air.

    After investigating Activity Monitor (thanks for the tip by the way) there is a process called dnssd that takes up about 98.8% CPU usage... insight?
  4. macrumors demi-god


    That's a Firefox add-on. You can kill the process and see if it comes back. If it still dominates CPU, disable it.
  5. macrumors member

    FIGURED IT OUT. There's a problem with printer drivers in Mountain Lion. dnssd is related to that. Once I uninstalled all my drivers, I was fine :)

    Thanks for your help!

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