5 Replies Latest reply: Feb 19, 2010 2:00 AM by Roald Hoolwerf
Mb1000 Level 1 (0 points)
Just got my brand-new iMac this week and I'm loving it! I am quite concerned, however, that the back of the computer gets very, very hot after a few hours of use (Internet, HD video, Photoshop, Parallels running Windows 7 64-bit). I'm used to electronics getting warm but this is HOT! My question is, Is this normal? Please help me!

I downloaded both iStat Nano and iStat Pro. RIght now they're giving me the following temperatures (sometimes the two widgets differ slightly and they due fluctuate as expected). This is as much info as I could find.

HD: Macintosh HD: 50°C/122℉ (went up to, I think, 59°C after a about 10 hours on 2 days ago)

CPU A/CPU: 42°C/108℉

GPU Diode: 61°C/142℉

GPU Heatsink: 59°C/139℉

Ambient: 23°C/74℉

Memory Controller: 55°C/135℉

Northbridge: 59°C/139℉

Optical Drive: 50°C/122℉

Power Supply 2: 61°C/142℉

My iMac has been on for a couple of hours. Are these temps normal? Thanks.

21.5-inch iMac (Late 2009), Mac OS X (10.6.2), Intel Core 2 Duo, 3.33 GHz, 8GB memory, 1 TB hard drive
  • elmac Level 5 (4,230 points)
    Hi, as stated in previous posts" the ali' mac is itself a heat sink & dissipator, a suggestion I made a while ago, run a small deskfan onto the back of your Mac...L
  • inandoutofgrace Level 3 (520 points)
    Your ambient room temperature probably is having an effect on your computer. Here are my current stats from iStat Pro:

    HD: 92 Fahrenheit
    CPU: 88
    Ambient: 59
    GPU Diode: 108
    GPU Heatsink: 104
    Mem Controller: 95
    Optical Drive: 85
    Power Supply: 101

    And as measured by a home thermometer, the room where I use my computer is 68 F.

    These are typical temps for my i7 iMac. If I'm doing something HD intensive, the HD temp can go over 100 but it rarely exceeds 105 or so. I've seen my CPU go up to 114 or 115 when using Handbrake but it usually runs 90-101 degrees. Usually the only components in my machine that seem to get hot and stay hot are the power supply and the HD (especially if it has been working hard).

    You might want to consider increasing the airflow near your computer (the small fan suggestion above is a good one) and looking into ways to lower the ambient temperature of the room your computer is in.

    Message was edited by: inandoutofgrace
  • DirtWarden Level 1 (0 points)
    Wow. All I can say is, you guys have "cool runnings" going on. Right now, I show:

    Ambient: 68
    CPU: 151
    GPU Diode: 156
    GPU Heatsink: 154
    Mem Controller: 138
    Optical Drive: 118
    Power Supply 2: 183

    All in farenheit, of course. That's a pretty HOT i7. Wonder if there's something wrong with it. I have AppleCare extended, so I'll let Apple worry about it, but it looks like I'm baking an Apple Pie right now. (Man, Apple Pie. I just made that up. I slay me...)

    Granted, I'm encoding a bunch of .AVI files into .MP4 right now with VisualHub and all 8 cores are MAXED OUT. My CPU Utilization is popping back and forth between 96% and 98%, so that explains some of it.

    Am I OK with these temps?
  • jamesholden Level 3 (710 points)
    All the figures above are fine, you can have a CPU running at up to about 90 degrees celsius without much problem.

    As the for the suggestion of having a fan blowing at the rear - dont! It'll make it worse. Imagine having a heat-sink with a fan blowing air back at the chip rather than sucking the heat away, it'll just mean that the heat can't escape.
  • Roald Hoolwerf Level 1 (40 points)
    Just ensure that your airducts are clear.
    The bottom of your iMac has the intake ducts, the long stripe at the back is the outgoing duct. Keep those clear (so don't put a lot of junk below your iMac) and the air will keep flowing.