Thats the point. It auto shut down cores!
Why waste money on more cores for it to shut down to perform the same if not worse performance than a X4. Since most games are mainly meant for dual cores with some optimized for tri and quad cores, six cores is pretty much irrelevant for now.
...so why not just have the extra cores? The money differential in just the CPU alone, and that's all we'd be talking about, is not that great. Games are only one software option...what about multi-tasking environments....your comments are a bit one dimensional IMO...now if you could unlock the two more cores on the quad and have the same functionailty as the X6 i'd grant you your point. Oh, and when you say performs worse than an X4, what do you mean by that? I certainly don't see that between my two setups and my THURBAN does BM faster than my DENEB, but in real world operation I couldn't tell which one I was sitting at without looking at device settings, they both have a max Ms VISTA 64 Ultimate rating of 5.9