Why am I Constantly Being Throttled?

[matty1551]

Is this normal? I've never noticed before but doing anything CPU intensive results in an almost immediate CPU throttle.

This is with a 2011 MBP 2.2Ghz quad core i7 running 10.8 with all updates.

My temperatures appear normal and my fans are not running loudly so I don't understand why this would be happening

My handbrake encode is estimating 3.5 hours for a single 1080P movie.

This is another test using "yes" commands in terminal to max out the CPU. There are 6 instances running but the temperature only rises slightly.

 

[Intell]

Is you machine plugged into power or running on the battery?

 

[someoneoutthere]

Is you machine plugged into power or running on the battery?

It seems to be plugged in - at least that's what the icon says.

 

[matty1551]

Always plugged in. I was using it in clamshell mode. I unhooked my external and ran the same tests again and the machine is increasing in clock speed and heating up as expected.

Not sure why the external display would cause this though.