Does the CPU TDP value reflect the same power usage even if the clock speeds are different?

Question

Okay guys, so the new Macbook Pro's just got released yesterday. Apple make it difficult, but I can reverse-engineer the CPU models from their limited spec-details...

So I can get a i7-6920HQ, or a i7-6820HQ. Both have a TDP of 45W, but the former runs at a single-threaded benchmark of ~12% higher. Source

My question comes from very limited knowledge on how TDP works. So my ROOT-question is this:

Will I get 12% performance boost at no additional cost to battery power usage?

Another way to ask this is, "Will the 6920 use exactly the same power as the 6820 whilst executing my workloads in shorter timeframes?"

Answer 1

The TDP means Thermal Design Power (or sometimes seen as Thermal Dissipation Power, but rarely in computers) and does not specify the consumption of the processor, but the cooler's capacity to dissipate heat away from the chip/surface it cools. Although it provides a rough estimate about the power draw of the processor, it doesn't necessarily mean so.
Intel and AMD have different actual definitions as to TDP.

As a matter of fact, the typical power consunmption of the 6920HQ is 36.56W, same as the 6820HQ. Generally, this is the same chip but a different bin - the better chip runs at a higher frequency while fitting in the same power envelope (36.56W typical).

To answer your question - without fine tuning it is safe to assume that yes, you will get these 12% performance in the same single-threaded benchmark at (approximately) no additional power cost. The reason is that when supplied with the same amount of power and same current, the better chip of the bin (branded the 6920HQ) runs stable at a higher clock speed.