even though it have the bio switch it will not unlock the extra shader . use gpuz and extract the alternate shader bio I can confirm that Sapphire be put a unlock bio on the card from the factory . however , even though this be the case the shader will not unlock . for that reason the card only get 3 star from I . people claim that you have to uninstall driver do not know what they be talk about ! there be no need to uninstall the driver to get the extra shader to unlock . just a head up it be pot luck you get one that will unlock and at this point I beleive AMD be laser out the extra shader on this GPU to try and get rid of the 6970 's in they stock and to push the 7xxx series card ...