13 Replies Latest reply: Feb 19, 2006 5:54 AM by Optimus
Peter Ammon Level 1 Level 1
I just purchased a new Intel iMac 2 GHz with the 256 MB video card and I love it, except that the fan is very eager to turn on and is much too loud. For example, doing nothing but running the Flurry screen saver for 10 minutes in a cool room will cause the fan to reach full power and noise. What's worse, the fan never stops or decreases in intensity, even if I let the computer sit idle with a disabled screen saver for hours. If I turn off the iMac, let it sit for a while, and then turn it back on, the fan is quiescent, until I start using the computer again. Even something as simple as typing in TextEdit will cause the fan to reach full blast in a few minutes.

Every other report I've seen says that the Intel iMac is very quiet, and I can't reproduce this problem on other Intel iMacs that I have access to, so I'm afraid that my unit is defective.

Reinstalling the OS from the DVDs didn't help, nor did zapping the PRAM. I'm out of ideas - any help?

Thanks in advance!

Intel iMac 20" Core Duo 2 GHz, 256 MB video card, 1 GB of RAM   Mac OS X (10.4.4)  
  • Glorfindeal Level 6 Level 6
    Your not going to get any help. You need to take it into an applestore somewhere and let them examine it.

  • The Ancients Level 7 Level 7
    Further to what Glorfindeal has stated: run the Hardware Test disc, and see if it notes any physical faults.

  • David Harney Level 1 Level 1
    When your fan(s) are activated, does your unit seem hot to the touch along the back of the case or the lower front below the display.
    The possibility exists that one of the sensors may be falsing. Also, what are you terming "excessive"?

    You might try restarting your Mac and immediately following your chime, hold down the command (apple) key next to the space bar and the 's' key simultaneously. On your model you will probably hear the fans at full (roar). At the prompt (word root #) type /sbin/fsck -fy ......NOTE: there is a space following the fsck when you type. Then press return.
    Make note of any errors reported.
    When the prompt (root #) comes up, type reboot

    See if anything beneficial occurs; I've seen OS reinstalled with the file system problematic and unchanged. Anything's possible on a new machine produced in quantity. Rare but possible. A lot of technology going on inside; Apple's one of the best.

    Also, open activity monitor and observe what happens coincidental with the fan actuation. The more observations you make ( your personal computer) the better you might be able to communicate this to a technician who might not be as familiar wih a newly released model.
    Yours may be one of the first reported instances of this.

    Macs and PC's everywhere at home and work. Mac OS X (10.4.4)
  • SueB1863 Level 1 Level 1
    This is, what, the fourth version of this design, and they still haven't solved the fan noise problem??

    Sorry, just amazed, that's all...
  • Glorfindeal Level 6 Level 6
    He probably has a lemon. My 3rd version has no fan problems at all. Don't make generalizations from 1 data point.

  • Fifty50 Level 1 Level 1
    Peter, this seems to be a typical symptom that most of the 20" iMacs have, since the 2nd (and possibly since the 1st) revision of the iMac G5. I have friends who have noticed the fan noise and even though it's not terribly bothersome, they have both decided to take it to an Apple Center and get it checked out. There's nothing really wrong with the iMac, but it turns out that replacing the power supply is the best course of action to reduce the sound.
  • imaccer Level 2 Level 2
    I'd call Applecare or take it in--they should fix it for you--it is definitely under warranty. Also, I'd go ahead and purchase the Apple Care for the three years--it has helped many people.
    Good luck. Keep us informed.
  • tthiel1 Level 2 Level 2
    Something is wrong with your intel imac. They are very quiet, even quieter than the 3rd Gen G5 imac. Take it in.
  • Fifty50 Level 1 Level 1
    to follow up on what tthiel1 said, there are reviews stating that the 17" model is quieter than the iMac G5, but this has always been the case. In my experience, most of the 20" models are much louder than the 17" models.
  • Frank D'Anna Level 1 Level 1
    I can confirm that my 20" Intel Mac with 1GB of Ram and 256 Video memory has been extremely quiet and the only time I hear anything is in a totally quiet room.

    My 17" iMac G5 rev A was like a jet engnie by comparison.
  • bimmerdude Level 1 Level 1
    I just went through a fan noise issue myself on a new intel iMac 20". The fans came on over the weekend and stayed on constantly for 2 days. Mostly running about 50% but adjusting up to full and down to low hum and back. Basically sounded like a hoover in the room. I restarted, shutdown, put it to sleep, ran permissions, disk verify, etc. and nothing worked. Finally put the hardware test in and it found a fault. As a last effort I decided to try unplugging it from the wall to see if something was being held even when shut down..and guess what...it worked. After I started it up again the fans were normal and I ran the hardware test again..No Fault!! I ran the system hard for an hour doing all kinds of video, photo, surfing, etc. and they stayed at the low hum that they had before this.

    So something was being maintained in the system as long as power was connected. So anyone with thier fans running fast for no reason give this a try and report back if it worked. I will report back if the problem shows up again.

    PowerMac MDD 1.25   Mac OS X (10.4.4)  
  • Peter Nardi Level 1 Level 1
    Here's my experience with fan noise:

    I have a 20" G5 iMac (seccond generation). I've owned it for about 9 months, and in the last month-or-so I started to notice a significant increase in the amount of "fan cycling." My kid plays Zoo Tycoon, which puts a heavy load on the processor and causes the fans to launch into the hoover effect after only a few minutes. I also noticed that even under light CPU loads (Safari, Mail) I would hear significant noise coming from the fans - not the noise that comes from the spinning fan making physical contact with something (a mechanical problem), but rather the blowing noise that comes from a fan running at high speed.

    Yesterday I decided to pull the back off to have a look inside. I didn't even have to turn the first screw to find the problem. The intake grating along the bottom was severely clogged with dust-bunnies. After a quick cleaning - plus using a can of compressed air to blow out the internals - the machine is whisper quite again. It even keeps quite under heavy loading, like hours of continuous Zoo Tycoon play.

    Now I know this doesn't explain fan speed/noise problems for folks who just took it out of the box, but if you've had your iMac more than three months and you notice your fan cycling high and low, you may want to try cleaning it. No secret that internal temperature regulation is very dependent on air flow, but it's the type of flow that matters. Low speed, high volume air flow is much more effective than high speed, low volume air flow at carrying away heat.

    It's great to have my old iMac back. I'm going to a quarterly cleaning schedule whether it needs it or not.

  • Optimus Level 2 Level 2
    I've said it once in another thread, and I'll say it here again, I am absolutely baffled by some of the responses some people post in these forums.

    You read one person make a claim regarding the fans, and you shreek with disbelief at this being the "forth version and they still haven't solved the fan noise problem". What is with the emphasis on "still" ... there is no fan noise from the Intel iMac's ... mine has been powered on non-stop since Tuesday when I got it home, with the display going to sleep after an hour and the machine NEVER sleeping but Hard Disks being allowed to sleep when possible.

    The machine is COLD to touch, there is NO fan noise, and the bottom line is that the user with a problem has a faulty iMac. Read reviews, do some research, know what you're talking about ... then comment. Don't read one persons fault and cry with dispair at the iMacs all being loud.

    I still can't believe some people are so naive.