Next generation AMD64s will be a completely revamped architecture as they have to modify the memory controller for DDR2 support...I believe all cores will be based on a 65nm multicore architecture, including a multicore FX-59
But yeah, this actually happened twice...first early Winchesters were hitting like 2.8GHz on <1.5vcore...then results started to decrease...and then the Venices were hitting 3.1Ghz on air with <1.4vcore