Quote Originally Posted by Calmatory View Post
Still it can't be possible to gain over 100% efficiency, unless the clockspeed somehow makes the chip more efficient as in cache/memory management etc. Thus it is impossible to get more than 100% increase in performance from 100% overclock etc.



Still over 100% efficiency in gain is impossible.
Technically it is. Eric Demers posted this

As for super-linear performance, it's possible -- The actual amount of cache is increased as well as the number of functional units. That means that it's very possible for data to stay in cache longer in xfire, than in regular rendering on a single card. That will lead to performance higher than 2x.

On average, we are seeing scaling in the 1.75 ~ 1.85 range for xfire. Of course, this is at higher resolutions and/or higher settings.
So it sounds like cache can cause performance to scale greater than linearly