Turbo Boost of 13" TB MBP i7 capped at 3.4GHz?

[pphilip]

Hello from a first time poster.

So, I finally got my new MBP (TB with i7) early this week and I found that mine doesn't boost to 3.6GHz (from 3.3 base) as advertised. My clock speed seems to top out at around 3.4, see attached screenshot. I used a Matlab simulation (single core) to generate the workload, while being plugged in. Even when the temperature is still relatively low, the clock does not increase beyond the 3.4GHz.

It might be that Matlab is not a good test environment (but the upper bound of 3.4 seems too consistent for that to be the case). It could also be the Intel Power Gadget misreporting the clock speed but I doubt it as well.

Is someone else observing something similar with their i7 or 3.1GHz i5?

Philip

 

[Yoshimura]

Maybe it was using 2 cores which limit turbo speed to 3.4.

 

[pphilip]

Thank you Yoshimura for your comment.

Matlab only uses multiple threads when you initialize a "parallel pool". I checked with the Activity Monitor and that is indeed the case with Matlab using 150% of the CPU in a single thread. I subsequently closed most of the other applications I had open, but the result was the same. (Although I might have seen a 3.42 once but couldn't replicate it.)