Finally done with the last of my midterms.

Turbo has 2 levels. It will up your multiplier by 1 or 2.

Upping by 1 seems to always be the case when it's under load. Even under multi-threaded load.

Upping by 2 only seems to happen when you have 1 thread that is locked to a single core.

My suitemate and I were just playing around with this on his 920. Running the program in multi-threaded mode always jacks it from 20 to 21.
Under single-threaded mode (without locking it to a single core), it still only goes up to 21.
If we lock it to one core (via processor affinity), then it will go up to 22 for short bursts.