We managed to find out that the latest revision of the K10 only needs 1.08V to work at its lowest 1.6 GHz clock. You need to get the voltages all the way to 1.38 to get the K10 Quad core to work at the desired 3.0 GHz speed and probably even more in order to make it pass the magical 3.0 GHz barrier.
This is a big success as the first revision, B0 needed 1.17V to work at 1.6 GHz and 1.31V to work at its maximum 2.4 GHz. The B1 revision was a bit better and it needed 1.12V to work at 1.6 GHz and 1.28V to work at 2.7 GHz clock.
The B2 stepping might be too young to be launched by August / September time, so I guess that the first batch of the CPU’s will probably use the B1 stepping, but then again AMD needs these high speeds more for Phenomes than Opterons.