as we know currently/for next future there will be no Support for multiple Graphic Cards ... APG will only recognize one... ... so one graphic Card with 6GB GPU Memory will give APG more power than 2 cheaper Cards with 3GB GPU Ram each.
now my question: the AMD Radeon HD 7990 does have 2 x 3 GB GDDR Memory... so 2 Cards in one Body... does APG now can work with 6 GB GDDR or only with 3GB GDDR?