So it seems Ncc-1709 in Xtremesystem got a QX9650 all four cores working on a EVGA 680i. And it even can be further overclocked. The CPU-Z validation proof is here, and the main thread is here.

The most interesting point of this story is , the BIOS of the EVGA 680i. It is an old version(P31), so the support of Yorkfield is not a BIOS update effect. We will keep and eye on this and maybe will also do a test to verify this issue later.