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username931
Whenever I use processor intensive tasks such as handbrake, crossover, and parallels, the CPU fan becomes hyperactive. When I recently tried to rip a video with instant handbrake the above happened and activity monitor displayed ~142 - 152 % CPU usage. I obviously can't have my CPU running like that for > 1hr.

I had previously noticed that the "about this mac" displayed my CPU as 3.6 GHz even though it is a 3.2 GHz (Intel SSE3 w/ hyperthreading). I cloned my boot partition and installed Jas 10.4.8. "About this mac" then displayed 3.2 GHz, and the prob was still there. I also updated to the "Nebukadnezar" kernel with no effect. I think the modified applesmbois.kext I installed for 10.4.8 prevents OS X from controlling the CPU fan, so it is fairly certain, I think, that it is actually overheating (and not some powermanagement error).

The same handbrake (DVD -> ipod mp4) coversion in windows only uses a max 50% cpu, and other than I new kernel I don't really know where to go from here.

EDIT: I notice a lot of faults when this happens
tidalpassion
Whenever I use processor intensive tasks such as handbrake, crossover, and parallels, the CPU fan becomes hyperactive. When I recently tried to rip a video with instant handbrake the above happened and activity monitor displayed ~142 - 152 % CPU usage. I obviously can't have my CPU running like that for > 1hr


Obviously? No. That's what should happen, at least with Handbrake. Video compression needs all the CPU it can get.

I suggest you read this:
http://en.wikipedia.org/wiki/Load_average

Having power-saving idle modes translates to more heat generation when the CPU is actually doing something. That's normal. Be grateful the CPU has lower-power modes and that the fan doesn't need to run full speed all the time. If the fan is too loud for you, consider a larger heatsink and/or not clocking quite so high.

There is a reason that Apple used the mobile version of the Core 2 Duo in the iMacs.
Heat generation and cooling system noise are among the things to consider when making design tradeoffs. Hand-in-hand with those is energy use. Those factors also come into play when deciding what GPU to use.

Having a CPU load above 1 (or 100%) per core simply means the task is CPU bound - it would get done quicker if the CPU were faster. It's not like it is being forced to do more than it can handle.
Fiendskull9
lol

and to put my two cents in...

it displaying 3.6 doesnt mean that its overclocking your processor

Soft clocking is dangerous in the first place, and its not actually overclocking your processor, its just a display error

-clay
DJ Commie
I don't suppose your motherboard has a dynamic overclocking setting, does it?
shakaru
You may need to go ahead and kernel flag the FSB settings.
Just boot with the flag "FSB=???" and replace the ? with your fsb settings. Fixed the same problem for me.
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