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