Just a wee report:

(dell xps 1645)
I discovered that if i dont set my MIN processor to 100% on my powerplan i am forever STUCK at 900MHz!!! even if i set it to min 80% it wont budge from 900MHz firm. Hence explains all my stutters here and there!

But when i set to 100% it stays at 900MHz at rest and then shoots up to 2.8GHz when required.

Environment:
plugged to AC power
reinstalled OS but also reinstalled all drivers

There is no driver for turboboost for studio XPS altho when i bought a studio (non XPS) for my brother it had a turboboost driver - i will find out from him if his laptop behaviour is the same ...

experience with other brands/models??? if this is across the board then everyone make sure you set to min 100% otherwise ... haha you are handicapped!!