12 Replies Latest reply: Aug 4, 2008 6:36 PM by ren390
ren390 Level 1 (0 points)

I just bought an Intel iMac 20-inch 2.66GHz around June of this year. My imac has been over heating. When I touch the back of it, it is extremely hot. This is not normal. I used smcFanControl to keep my imac cool. I feel that I shouldn't have to install smcFanControl in order to keep it cool. I am running photoshop, flash cs3 and safari. I do not want a band aid on my situation, I just want my imac replaced with a new one. 50 degrees c and more. I feel like my imac is about to explode.

Please help if anyone has any answers.

Thank you.

Message was edited by: ren390

Intel iMac 20-inch, Mac OS X (10.5.4), 2.66GHz Intel Core 2 Duo
  • den.thed Level 7 (25,970 points)
    Hello ren

    It's normal for the aluminum case to feel hotter on the outside than the earlier white plastic iMac models for example. What does the iStat Pro widget say your internal temperatures are for the GPU, CPU, HD and at what speeds are you running the fans with smcFan Control?


    Apple Discussions is a user to user forum so we can't help you get a replacement iMac, you'll need to contact Apple at.


    Also note: Apple systems are covered under warranty for 1 year and 3 years with Apple Care, so if and when it Explodes just take it in to be repaired!

  • ren390 Level 1 (0 points)
    I am running all fan speeds at 3400 in smcfancontrol.

    Message was edited by: ren390
  • den.thed Level 7 (25,970 points)
    I feel your discontent, at 3400 rpm those fans must be pretty annoying. Again use the iStatpro widget to see how hot each area of the iMac is! It's not uncommon for the GPU to run at as much as 70C, but you do want to keep your CPU and HD in the 50C range!
  • ren390 Level 1 (0 points)
    Thank you den.thed.

    When i get home, I will install istat and see what happens.
  • den.thed Level 7 (25,970 points)
    Your welcome!

    Most of us here are only running our fan speeds up only 2 to 3 hundred rpm over default, 1400 to 1600 rpm with great results.
  • sekitori25 Level 1 (0 points)
    My 24 inch aluminum iMac also seems very warm, especially on the upper left hand corner. The iStat pro indicates that the GPU diode which runs hotter than any other temperature, usually operates in the 130° F range but it always lowers a few degrees when it gets close to 140. The GPU diode can get up into the high 150° F area when the computer is working very hard over a long period of time but again, when it gets that warm, it cools down. The thermostat regulating the temperature seems to be doing what it's supposed to. I called Apple Care and they said those "extremely hot" temperatures were in normal limits and if the temps exceeded those limits, the computer would shut down. Mine has never shut down. By the way, I do not use the smc Fan Control. My CPU and hard drive fans run at close to 1200 rpm.

    I was told when I bought this iMac that it will seem very hot while it's running and that's to be expected. My big "mistake" has been to constantly refer to the temperatures indicated in the iStat pro. When I first noticed that the temperatures seemed quite high, it drove me kind of crazy. But now that I realize that the computer is operating within normal ranges, it doesn't bother me any longer. If you feel that your aluminum iMac is running too hot and if Apple replaces it, don't be surprised if your new one runs just as hot. It's just the nature of this particular computer. In my opinion, 50° C doesn't sound too bad and compared to the temperatures mine runs, it seems quite cool.
  • crazy mac dude Level 1 (0 points)
    try putting in more ram it looks like you are running a'lot of big programs
  • musashi88 Level 2 (455 points)
    hi ren
    iStat Pro is great but I like to also use Temperature Monitor (link below) as it gives me a lot more temps including the hottest spot, Power Supply Position 1. It also gives displays the ambient temp. My 20" gets hot too and my fans are:

    2004 ODD
    2219 HDD
    2205 CPU

    I like to keep my temps under 50-60ºC or 122-140ºF.

  • Armik Level 1 (0 points)
    That's NOTHING!! I just bought a 24" iMac @ 3.06ghz with 4gb ram and a 1TB HDD, and it hasn't even been 2 weeks yet and smcFanController showed that my temperature was 88.3 degrees celcius (about 190 Fahrenheit!!!!). I was scared outta my mind when i heard the fans whirl that loud!! All i was doing was running imovie on its own and it was just importing some thumbnails from iphoto or something like that. Im a mac switcher and to think this is what i was bragging about moving over to Apple about is not cool! ill give it some more time and if its persistant ill contact Apple.
  • elmac Level 5 (4,230 points)
    Hi, "running hot" iMac users. I agree with running the 3rd party Apps etc. But if you are unhappy with the heat generation -> Apple (Apple Help or Genius Bar) do not leave it too long, otherwise many other components might be heat affected. Who know's Apple might replace something and the heat may have affected the "next to" component..then that is the weak link.."getIt-Done"
    Sadly, I hope never brings a solution....L
  • George Peters Level 4 (3,165 points)
    You need to install iStat Pro and find out what all of your temperatures are because the SMCFC itself only displays one temperature.


  • ren390 Level 1 (0 points)
    Thank you all. So far everything looks good keeping all fans at 2500.

    When I check my temp, they are all under 45c but the power supply goes up to 55c.