14 Replies Latest reply: Jun 27, 2012 5:08 PM by Qisti
Damowhite666 Level 1 Level 1 (0 points)

Hello I have brought a new iMac 27'' the i5 model. I have noticed that the fans never change speed no matter how hot my processor gets ? Is this normal ? I have ran prime 95 and istat pro to check the temps and fan speeds. Nothing changes apart from the temperature. I could really use the help here. Thanks.


iMac, Mac OS X (10.7.3)
  • 1. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    Right now my CPU is at 65'c and my fan speed is 939rpm. I really think that it should be spining a lot faster than that.

  • 2. Re: Fans never spin any faster iMac overheating ?
    Klaus1 Level 8 Level 8 (44,505 points)

    65 C is fine. It is not overheating.

     

    (Mine is at 66 C so there!)

  • 3. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    Should the fans not adjust even a little ? I mean right now when doing nothing or just browsing the web it get around 40'c and the CPU fan spins at 939rpm. Then when I run the prime 95 test it gets 65'c hot and no change to the fan speed. Sure thats okay ?

  • 4. Re: Fans never spin any faster iMac overheating ?
    X423424X Level 6 Level 6 (14,190 points)

    Not sure what is normal nor how the fan control brackets temp ranges if it doesn't have a temp vs. speed continuous function.

     

    You could always install smcFanControl.

     

    But try a smc reset first.

  • 5. Re: Fans never spin any faster iMac overheating ?
    John Galt Level 8 Level 8 (36,425 points)

    Damowhite666, I wondered the same thing, I even ran Geekbench stess tests for hours on end and the iMac barely gets warm. iStat Pro indicates about the same - mid 60s C and the fans do not become audible.

     

    I was concerned something was broken so I ran Apple Hardware Test. It exercises all the fans and they get LOUD.

     

    The i5 is a fantastic processor and iMac simply runs cool. The aluminum enclosure dissipates heat very effectively. It's normal.

     

    You're probably accustomed to (ahem) lesser computers.

  • 6. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    I tired that. I've seen that I shouldn't need a fan controller software, the iMac should take care of it self ?

  • 7. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    How would I run the apple hardware test ? I'd just like to see if they have the power to spin as they should ? It's kind of worrying as I've not heard my fans or seen them spin up at all doing anything.

  • 8. Re: Fans never spin any faster iMac overheating ?
    John Galt Level 8 Level 8 (36,425 points)

    To run Apple Hardware Test reboot your computer whilst holding the D key.

     

    Read about it: http://support.apple.com/kb/HT1509

     

    This is how she runs all day long:

     

    Screen Shot 2012-03-31 at 2.10.00 AM.png

     

    Geekbench brings the CPU up to 65° or so. That's nothing.

  • 9. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    Will that work with a wireless keyboard or would I need wired ? Also. Your cpu fan spins faster than mine at 939rpm, different kind of mac ?

  • 10. Re: Fans never spin any faster iMac overheating ?
    John Galt Level 8 Level 8 (36,425 points)

    This one is a 21" i7 so maybe your bigger case is more conducive to cooling. I am listening to Internet radio and some other things are running but the fans stay pretty much as they are.

     

    The D key works to boot AHT, wired or BT keyboard makes no difference, I have tried it with both.

     

    Pardon my assumptions Damowhite666 but it seems as though you are new to Macs. Please do not bring any preconceived notions regarding the proper care and feeding of computers to the Mac world, especially when it comes to anti-virus utilities, cleaners, "scanners", "optimizers" or such junk. Macs are designed from the ground up to be neglected so you can simply concentrate on using them to do whatever it is you do. Stop obsessing.

     

    You have the computer equivalent of a Porsche that will go for a million miles without so much as an oil change. It is the product of decades of relentless and uncompromising pursuit of engineering and design excellence. Don't chop it up by installing suicide doors and spinner hubcaps.

     

    By comparison I have a two year old client-supplied HP Windows laptop as well. It sounds like starting a diesel dump truck on a winter morning. Works like it too.

  • 11. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    I ran the test all seemed to be fine since after it ran I didn't get any errors which is great. Thanks for the help.

    Kind of one of the reasons why i brought a mac, the only utility I installed that I can put trust in is a program called "ccleaner" I've used it in windows. I won't have the need to install anything else. I have had this iMac for two days, I'm still getting to how things work, I just love how everything is smooth and how easy things can be done. I should of saved all my money and brought a Mac ages ago.

     

    Anyway. Thanks for replying so fast, seems as though it's normal. 

  • 12. Re: Fans never spin any faster iMac overheating ?
    John Galt Level 8 Level 8 (36,425 points)

    CCleaner is totally unnecessary. Everything it does the Mac OS has already been doing for at least the past three major OS releases.

     

    I recommend you get rid of it ASAP. It is a prime example of a Windows software vendor porting its preconceived ideas to the Mac platform.

     

    The very same utilities that are beneficial and necessary in Windows often cause unending misery for the Mac. Don't go down that road. Search Apple Support Communities for CCleaner and you will find the best thing people have to report is that it is benign. Like a tumor.

     

    Here are some maintenance and trobleshooting tips from Apple

     

    General Mac maintenance: Tips to keep your Mac in top form

     

    General purpose Mac troubleshooting guide: Isolating issues in Mac OS X

     

    Enjoy your iMac and if you ever suspect something is wrong with it don't panic, don't go downloading some magical cure-all, search here for help first.

  • 13. Re: Fans never spin any faster iMac overheating ?
    Damowhite666 Level 1 Level 1 (0 points)

    Thanks for the help. Will do.

  • 14. Re: Fans never spin any faster iMac overheating ?
    Qisti Level 1 Level 1 (0 points)

    I have similar problems. My imac is early 2008 24". Fans never spin any faster eventough cpu temp is 84C loaded. I believe this is very hot for a processor.

     

    I installed smcfancontrol and increased cpu fan speed to 1500RPM default but no effect. The temperature I mentioned is after smcfancontrolled is installed but fan speed never go higher than that. Does the mac cpu designed to withstand 84C for long periods?