http://www.thinkcomputers.org/amd-hawaii-gpu-die-shot-analyzed/

A
recent article from Thinkcomputers.org reveals that the Hawaii XT core is still a few compute units shy of it's maximum potential. The specific reasoning behind this is unknown, but this bodes exceptionally well for AMD's Hawaii core and leaves even more room for improvement, potentially fully ousting the like of 780Ti. Hopefully the cores will be fully utilized before the release of Maxwell, though they may have been left on the table to help compete with Maxwell as it's released. Only time will tell.