AMD showed off the upcoming Phenom II X4 processors running at stock and overclocked speeds

The first leaks were that the Phenom II could hit 4 GHz on air cooling alone, though we obviously wonder how extreme that air cooling is. Well today AMD had some actual demonstrations at their gathering, and the Phenom II was able to hit 5 GHz at 1.6v by using dry ice cooling. Dry ice is CO2, and it goes directly from solid to gas (sublimation) at a temperature of -109.3 F (-78.5C for the rest of the world) at 1 atmosphere. So with some pretty extreme cooling (non-LN) the Phenom II does show that it has some legs in the clock speed department.

AMD shows Phenom II running over 6.0 GHz