6 Replies Latest reply: Aug 20, 2012 11:38 AM by baltwo
stumpy007 Level 1 (0 points)

I have bought my first IMac.  I set it up yesterday but noticed the top of the screen gets really hot, so hot after 30 minutes you cannot leave you hand on it for too long.  Is this normal?

iMac, OS X Mountain Lion
  • rkaufmann87 Level 9 (53,585 points)

    Yes it is and will not harm your computer. If you are worried please download and install iStatPro (Google it) and post the exact temps your machine has. Apple builds in lots of fans (silent for the most part) into your iMac and uses software safeguards to  protect your system from actually overheating. If it senses it is too hot you will receive a warning and if that is ignored it will shut down however that is VERY extreme and there is almost a 100% chance you will never experience that behavior.

  • MichelPM Level 6 (10,645 points)

    Some users here just accept that the higher temps are just fine and dandy.

    I do not.

    Apple designers and engineers under designed the venting system and, IMHO, the aluminum enclosure keeps just as much heat inside the iMac as it vents or conducts to the outside.

    And they were more concerned about keeping the iMac line fan noise free like previous models.

    What some users here fail to understand is that older versions of the iMac had a much better venting/ cooling by having more outside openings to convect the heat outward. This is no longer true of the current iMac.design.

    The Apple designers went with this ultra clean minimalist design that designing extra venti holes or slots in the back of the iMac was considered a no-no. This new iMacs need more outward venting from the back. They could've had the thin opening venting that it has across the to and put this type of vent on the entire back panel periphery of the iMac.

    I am sure THAT woulld've worked much better, but Apple designers didn't do this.

    If your iMac is in a warm location like mine, or if the higher temps worry you, I would suggest you search, install and use SMC Fan control.

    I am going to keep saying this about the new iMac designs.

    They run entirely too hot for their good! Period.!

    I have used and owned six different Macs over a twenty year period.

    I have never had a Mac run as warm/hot as these new iMacs do.


    They just run too hot and basically the heat from inside the iMac is slow roasting the iMacs internal components to failure over what I feel is a not very long lifespan!

    Make your iMac run longer and elimate some of the risk of component failure from too warm/hot a computer.

    Just run the SMC Fan Control to ramp up the speed of the iMac's internal fans.

    The iMac won't be completely silent running any longer, but should still be, relatively, quiet enough.

    It dosen't hurt the iMac or the fans to run this control to speed up the fans to further cool the innards of your iMac.

    You can't damage anything as long as you stay conservative with the fan speeds to keep the fans from prematurely burning up.

    That said, I would only run the fans 200-600 rpms faster than Apple's default settings.

    Not exceeding 2000 rpms for any of the fans. You could ramp up the HD and CPU fans to 1800 rpms if you feel these might still be a little high.

    These fan  settings will lower the temps to an acceptable level and still keep the iMac quiet enough and keep from excessively sucking in extra dust, dirt and lint into your iMac.

    Good Luck!

  • rkaufmann87 Level 9 (53,585 points)

    Nice rant, totally incorrect and unfounded but nice rant.

  • MichelPM Level 6 (10,645 points)

    So, you're basically saying that you don't mind that vital components in your iMac are running in an internal environment of at least 110 degrees to 120 degrees Fahrenheit or slightly higher?

    You do not mind that your HD and CPU are continually subjected to these types of temperatures.

    You think Apple really knows what they are doing.

    Apple has made plenty of mistakes over the years. Under engineering the venting/cooling system in the new iMac designs may prove, down the road, to be another error.

    How well do you think YOU could work without issues in an environment this hot!

    Electronic components do not like this type of environment, either.

    No small mechanical or electrical components function well or last long when constantly operating in an overly hot, enclosed environment.

    And as tight as they pack the components into the new iMac design, the heat issues amplify in a tightly enclosed environment.

    Before I ramped up the fans in my iMac, the Northbridge component of my iMac was running at or close to 160 degrees Fahrenheit! I have gotten this down to about 140 degrees, but I am still concerned.

    I realize that computer electronic components generate some heat, but I still make my my stand and contend that the iMac's just have too much generated heat for them to have any decent longevity or have premature component failure.

    I owned a G4 MDD for about 10 years and never generated this kind of heat and never had a component failure.

    Do you think the new style iMac's will last this long running as they do now?

    Me don't think so.

    Again, My opinion.

    Do what you will.

  • rkaufmann87 Level 9 (53,585 points)

    My aluminum iMac is 5+ years old and had NEVER been one bit of trouble, so do I trust Apple knows what they're doing....you bet!!!!

  • baltwo Level 9 (62,210 points)

    MichelPM wrote:

    So, you're basically saying that you don't mind that vital components in your iMac are running in an internal environment of at least 110 degrees to 120 degrees Fahrenheit or slightly higher?

    Yes, that's totally normal. I use Temp Monitor and the only thing with min and max temps are the CPU cores, which BTW is 100°C. If you can find Apple's operating temp specs and they show that 120°F exceeds them, than post that info and the source. Much to do about nothing. Here are my stats, running ML.


    ML temps.png