iMac safe temperatures

Question

Level 1

5 points

iMac safe temperatures

Whenever I run any graphics/cd drive/processor intensive activity (games), my iMac heats up to an extreme temperature. According to iStat pro the computer's power supply temp can get up to almost 180º F. my Hard Drive and GPU temps usually hover around 140º-145º F for the Hard Drive and 150º for the GPU temp sensors. The temperature goes back down to normal levels about 30min to an hour after I finish doing whatever I was doing, but it seems from looking over these boards that temperatures this high may be problematic. Are these temps safe, or should I stop playing games on my iMac?

Intel iBook 20" 2.4 gHz, Mac OS X (10.5.2)

Posted on Apr 15, 2008 12:41 AM

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Answer 1

The Looby

Level 4

1,285 points

Apr 15, 2008 8:37 AM in response to abriggsknox

abriggsknox wrote:

... my Hard Drive and GPU temps usually hover around 140º-145º F for the Hard Drive ...

... Are these temps safe ...?

NO. Not safe. Every hard drive used in iMacs is specified (by the drive manufacturer) for
a maximum ambient operating temp of either 55C or 60C (131F or 140F), depending on
the specific drive model. "HD Bay 1" is the ambient temperature seen by the drive.

For more information, search the +Intel-based iMac+ forum for "smcFanControl."

Looby

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Answer 2

abriggsknox Author

Level 1

5 points

Apr 15, 2008 9:32 AM in response to The Looby

Thanks for your help. I installed smcFanControl 2.1.2 and it seems to be working fine. By increasing cpu and hd fan speed by 300 rpm (to 1500) i've already noticed some temperature drop in my power supply (usually the hottest component and the one that gives me the most worry).

On a related note however, how fast should I be running the fans. I have read that increasing fan speed too much for too long can cause the fan life to decrease significantly, but how fast is too fast? 1000 rpm? 2000? I'd like to run the fans as fast as necessary when playing games in order to keep things cool.

Also, when I am playing games the computer seems to get the hottest in the top left corner. Is this where the power supply temp sensor is located? Even when this is at it's hottest (almost too hot to touch) the rest of the machine seems rather normal.

Finally, I also run Windows XP through boot camp to play a couple of games and also do statistics work. Does anyone know of any windows fan control programs that will do the same thing as smcfancontrol so I can run up the fans in windows?

Message was edited by: abriggsknox

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Answer 3

Apr 15, 2008 9:32 AM in response to abriggsknox

Which model iMac do you have?

George

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Answer 4

abriggsknox Author

Level 1

5 points

Apr 15, 2008 9:33 AM in response to George Peters

20" 2.4 ghz intel

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Answer 5

abriggsknox Author

Level 1

5 points

Apr 15, 2008 9:56 AM in response to abriggsknox

Update: after running my computer for about 45 minutes (not doing anything except surfing the internet) with my fan minimum speeds set at 1500, 1500, 1000, my power supply is up to 59ºC. Is this normal?

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Answer 6

Apr 15, 2008 10:10 AM in response to abriggsknox

A few hundred rpm will be fine. Personally I adjust the fans up as much as needed to keep the machine cool. The power supply is located in the upper left hand side right above the CPU so that side will always feel warmer. The CPU fan provides cooling for the CPU, GPU, and the PS. I generally try and keep my temps lower than 50C particularly the hard drive. The way SMCFanControl works is it changes the default fan speeds in the firmware so even when you restart and boot into Windows the last set fan speeds should stay unchanged.

Here are some examples of mine:
http://ftp.georgetek.com/George/Temps_Before.png
http://ftp.georgetek.com/George/SMCFanControlDefault1.png
http://ftp.georgetek.com/George/Temps_Current.png (after)

George

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Answer 7

abriggsknox Author

Level 1

5 points

Apr 15, 2008 10:24 AM in response to George Peters

Thanks for all your help. I'll monkey around with the fan settings to find a good minimum setting for gaming and for just regular use!

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