You may want to re-read my posting, your reply suggests that you misunderstood.
Wording it slightly different: I mentioned that both in the 2010 and the 2011 model the fan under Windows speeds up a lot later (= at a higher temperature) than under OS X.
In other words: Nothing to do with TDP rating of the CPU or a GPU switched on or off, purely with: at what temperature the fan starts to speed up.