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I have heard there is software that drops temperature on Mac OS X without sacrificing performance...

Is that true and if yes can somebody name it?

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Search for a program that adjusts fan speed for the cpu. Otherwise the only way to cool it is by reducing power to the cpu. – jer.salamon Jul 26 '10 at 11:52
@jer.salamon While your comment is correct in general, it could be that there is some program which can change the processor's frequency based on load so well that user doesn't notice performance difference. – AndrejaKo Jul 26 '10 at 11:55
That is true, but it generally wont reduce the temperature more then a couple degrees without changing the power to the processor. – jer.salamon Jul 26 '10 at 12:04
up vote 3 down vote accepted

Personally I use smcFanControl to control the speeds of the fans on my Macs when necessary. You can set them to run at a higher than normal value if you find the computer runs too hot for your taste.

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Instructions are here.

Basically you need to edit some config files. You could shorten the life of your fan by doing it though.

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Summary: This change increases the fan speed, apparently without adding much noise. Potential downsides are fan power consumption and more wear on the fan, but that sounds quite acceptable. – Torben Gundtofte-Bruun Jul 26 '10 at 12:14
Can somebody post the instructions? They are in a pdf and you need to be logged in.There is also a post in this but the explanation is not so straight forward...thanks! – rabidmachine9 Jul 26 '10 at 15:45
Fans are cheap, HDs and other components expensive. It's worth sacrificing a fan for a HD. – alimack Sep 2 '10 at 10:52
Good point, @alimack. – JNK Sep 2 '10 at 12:02

CoolBookController, $10

It lowers the voltage without effecting performance and, optionally, throttles. My 2007 White Macbook was overheating to point of shutting off (about 90C), and CoolBookController was a big help. Throttling is intelligent and transparent.

The only two gotchas are: Don't crank up throttling all the way and play large HD movie files -- it will stutter.

The interface is clunky and not intuitive, but the defaults work just fine. You shouldn't have to change the voltages by hand.

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this also sounds good...I wish it was free but I would consider it if my macbook was shutting off – rabidmachine9 Jul 27 '10 at 11:11

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