at what temperatures do your fans speed up?

Discussion in 'MacBook Pro' started by red321red321, Sep 24, 2013.

  1. red321red321 macrumors regular

    Joined:
    Jun 3, 2013
  2. GGJstudios macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #2
    They don't spin up at a particular temp. If you're not already doing so, use iStat Pro (free) or iStat Menus ($16) to get accurate readings of your temps, fan speeds, etc., rather than relying on your sense of touch or sound. A forum member has posted a copy of iStat Pro that has been "tweaked" to enhance compatibility with Mountain Lion. You can download it here.
    The Intel processors used in Macs are designed to automatically shut down to prevent damage if they truly overheat. CPU Tjmax = 105C (221F), GPU Tjmax = 100C (212F) on i3, i5, i7 processors. (Source: Intel)
    Unless there is a rare defect in a Mac, most temps are well within the normal operating range, considering the workload being put on it. Websites with Flash content, games and other multimedia apps will put higher demand on the CPU/GPU, generating more heat. This is normal. If you're constantly putting high demands on your system, such as gaming or other multimedia tasks, expect temps to rise and fans to spin up accordingly. It's just your Mac doing its job to maintain temps within the normal range.
    It is also quite normal for your Mac to become extremely hot to the touch during intensive operations. The aluminum body transfers heat more effectively than other materials used in computer casings, so you will feel the heat more. This doesn't indicate that it's overheating and will not harm the computer to be hot to the touch.
    Your fans are always on when your Mac is on, spinning at a minimum of 2000 rpm (for MBPs) or 1800 rpm (for MBAs, MBs and minis), or 1200 for the newest MBAs. Older iMacs have 3 fans with minimum speeds in the 800-1200 range, while the newest iMacs have a single fan, spinning at a minimum of about 1400 rpm. They will spin faster as needed to keep temps at a safe level. If your fans are spinning up without increased heat, try resetting the SMC. (PRAM/NVRAM has nothing to do with these issues, so resetting it will not help.)
    The intake and exhaust vents are in the back of the computer near the hinge on all Mac notebooks (except the new MBP with retina display, which has intake vents along the sides at the bottom). The iMac vent is a slot on the back near the top of the computer. Make sure the vents remain unblocked to allow your computer to perform at its best. For Flash-related issues:
     
  3. The Unseen macrumors member

    The Unseen

    Joined:
    Jun 24, 2012
    Location:
    Naples, Italy
    #3
    Im my MBP 15'' Late 2011 they speed up at 80 celsius degrees (according to istat menu)
     
  4. GGJstudios macrumors Westmere

    GGJstudios

    Joined:
    May 16, 2008
    #4
    Temps can get even higher than that without fans spinning up. If temps spike, the fans may not spin up. Usually, temps must be sustained at a high enough level before fans spin faster. Also, fans can spin faster at temps lower than 80C. There is no fixed temperature that will always trigger faster fan speeds.
     
  5. The Unseen macrumors member

    The Unseen

    Joined:
    Jun 24, 2012
    Location:
    Naples, Italy
    #5
    I know that the speed change can start at various temperatures, but usually it starts around 80-82C.

    I haven't said that they go slowly when the temp goes lower than 80C.

    My opinion on the behavior of the fans under Mac OSX is that it would not be necessary to wait 80 degrees celsius and more for the fans to spin at 3500 rpm and more.

    The ideal would be to make it clear to the computer what type of operation is taking place (for example a videogame) and to start the fans to a regime medium before reaching a temperature close to that of the operating limit. I know this is not possible, I usually make this with SMC Fan Control, but I honestly do not think that the current default system is the most logical, especially for the fact that at a speed of 3500 rpm the fans are still almost inaudible, then increasing before the 80C and more, do not penalize the silence of the Mac.
     

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