What I can´t understand from an engineering stand point:

FX-8150: 294mm˛
i7 2600K: 216mm˛ with IGP

Of corse we don´t know the transistor count in FX-8150 or the density of Globalfoundries process, but still is a major difference in die size for less overall performance (assuming the leaks are from a final plataform).

May XOP and FMA4 be responsible for this die size?