Fans not slowing down!

Discussion in 'OS X Mountain Lion (10.8)' started by InfiniteLoopy, Aug 8, 2012.

  1. macrumors 6502

    Joined:
    Dec 14, 2010
    #1
    Before installing ML, I installed an SSD and moved my HDD to an Optibay-like holder.
    I'm finding that my MacBook's fans are spinning a lot more than they did in Lion.
    It seems that the fans cannot slow down when needed, they seem to spin up when required but then just stay at a high rpm, even when the MacBook is idle.

    If I put the Mac to sleep for a few seconds, and waken it as soon as the fans have stopped, they are back at 2000rpm, which proves that the cooling is not needed.

    Is this a ML problem or maybe a hardware problem?

    A few stats:

    Start from cold boot:
    HDD 25C
    CPU 65C
    Fans 2000rpm

    Using Safari, Pages and Numbers:
    HDD 35C
    CPU 75C
    Fans 3800rpm (can go up to 6000rpm)

    Help!
     
  2. macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #2
    Try resetting the SMC.
     
  3. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #3
    Thanks, I'd already done that and have just retried it.
    Upon reboot, fans were already in the 3000s and rising. I put the MacBook to sleep and the fans stopped after 5 seconds. I woke it up and they are staying in the 2000s for now.

    I'm guessing this is a ML issue?
     
  4. macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #4
    It looks more like you have processes that are pushing your CPU, driving up temps. The next time the fans spin up:
    1. Launch Activity Monitor
    2. Change "My Processes" at the top to "All Processes"
    3. Click on the CPU column heading once or twice, so the arrow points downward (highest values on top).
    4. Click on the System Memory tab at the bottom.
    5. Take a screen shot of the entire Activity Monitor window, then scroll down to see the rest of the list, take another screen shot
    6. Post your screenshots.
     
  5. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #5
    Well.

    I've been trying to get the fans up! Usually opening Safari and Pages will do it but not this time.
    I even tried watching HD trailers in the app of death (iTunes) but the fans barely went over 2000rpm.

    Finally, watching a 1080p film in iMovie fullscreen (with the above and Aperture open) got the fans revving and the CPU jumped to 80C.
    I quit iMovie and watched a fullscreen slideshow in Aperture, as I could hear the fans slowing down.
    I'm now at:

    CPU 65C
    HDD 35C
    Fans 2000rpm

    It can only be the SMC reset yesterday that solved it. I'll post again if I get any more problems.

    Thanks, :)
     
  6. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #6
    Well the fans are still spinning for no reason. It happens every day.

    Right now:
    CPU 75C
    HDD 35C
    Fans in the 4000s.

    If I put the MacBook to sleep, the fans stop and when I waken it, they stay in the 2000s ... but sometimes speed up again.


    Any ideas?
    ML bug?
     
  7. macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #7
    They're not spinning for no reason. With your CPU at 75C, it's normal that your fans may spin faster. Look at the processes you have running, as I suggested earlier.
     
  8. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #8
    Hi,

    I did check.
    There are no processes that are using more than 5% of the CPU and I have more than 5GB of free system memory.

    Maybe it's simply the summer heat (though it's a strange coincidence). If not, could the optibay/HDD or SSD be creating a situation where the fans need to work more?
     
  9. macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #9
    Did you follow all the instructions? Post a screen shot.
     
  10. Guest

    Joined:
    Apr 17, 2005
    Location:
    Currently in Switzerland
    #10
    Check NOT ONLY your own processes, but also the root ones - select the corresponding tab in Activity Monitor to see all processes.
     
  11. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #11
    The fans have been good for the past couple of days.
    Yesterday, I was using Aperture in fullscreen mode and the fans sped up, but eventually slowed down again.

    I'll post screenshots if/when problems arise again... :cool:
     
  12. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #12
    I'm still not satisfied with the fans.

    I'll do a recap and post some further info here:

    Before installing ML, I installed an SSD and moved my HDD to an optibay-like holder.

    Ever since doing these changes and installing ML, my 2008 Unibody MacBook is noticeably hotter in the back left corner, where the Magsafe, Ethernet, USB and Mini DisplayPort have connections plugged in.

    This results in fans revving up to 6000rpm for no reason, while the CPU gets to around 70C.

    I initially thought that this was an ML issue as putting the MacBook to sleep immediately dropped the fans to 2000rpm, remaining that way once I woke it again (for a while).

    However, it seems that some apps in ML, notably Numbers '09, are using up to 80%(!!!) of the CPU when in use, therefore pushing up the temperature of the CPU and the fans' rpm. Quitting Numbers gradually reduces the fans back to 2000rpm.

    I'm also seeing Safari use the CPU extensively, both Safari and Safari Web Content briefly occupy up to 50% of the CPU when clicking on links on MacRumors. (I don't have Flash installed.)

    Is there a solution to this? Has anyone else experienced this? Any thoughts on the hotter left back side?

    Also, for the first time this week, I've experienced upon a failed boot (or possibly a failed previous shutdown) a back screen of death. It was a screen of code and error messages reminiscent of a Windows BSOD, but on a black screen. Any ideas?
     
  13. macrumors newbie

    Joined:
    Sep 16, 2012
    Location:
    Netherlands (Europe)
    #13
    My situation is very similar. The only diffrence is that I have a mbp13'' 2009. Do you still have this problem or were you able to fix it?
     
  14. macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #14
    Read posts #2 and #4.
     
  15. macrumors newbie

    Joined:
    Sep 16, 2012
    Location:
    Netherlands (Europe)
    #15
    I have resetted the SMC. My setup is almost the same the only diffrence is that I have a 09 model mbp 13''. I also have an ssd and the hdd in an optibay.

    The problem is that the fans dont slow down when the cpu gets colder. The fan stays at 6200rpm even if the cpu cools down to 70c, or even colder. I have the SSD for over a year and it always worked properly. I also think that the problems started around the time that I installed mountain lion.

    I thought that it could have something to do with the HHD in the optibay, but im not sure. So I hope that the topic starter reads this and could tell me how he fixed the fact that the fans don't slow down when the computer gets colder.
     
  16. aliensporebomb, Sep 17, 2012
    Last edited: Sep 17, 2012

    macrumors 65816

    aliensporebomb

    Joined:
    Jun 19, 2005
    Location:
    Minneapolis, MN, USA, Urth
    #16
    Thinking....

    There were a number of things I've noticed along these lines but that the CPU fan seems to spin about 1/3 to 2/3 faster under Mountain Lion than under Lion or Snow Leopard before it.

    I've tried some of the processes but next-up I'll have to look at resetting the SMC.

    SMC reset: Now we'll put the machine under load for a bit to see what happens, but not too high a load.

    Update: sure seems like it's higher than it ever was under Lion or Snow Leopard.
     
  17. thread starter macrumors 6502

    Joined:
    Dec 14, 2010
    #17
    A while back, I switched to using the MacBook open, when attached to an external screen. It seems that this helps the air flow. Yes, sometimes the fans spin up but they also decrease their speed again eventually. I think opening your MacBook may help some of you with a similar problem.
     

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