It is likely that 3.2ghz is close to practical ceiling for these CPU cores for some technical reason. It's not about thermal headroom, but the very ability of t

It is likely that 3.2ghz is close to practical ceiling for these CPU cores for some technical reason. It's not about thermal headroom, but the very ability of the circuitry to run at faster speeds. It has been speculated that one way how Apple achieves their impressive perf/watt is to use logic gate arrangements that can only run at low frequency but bring massive wins in power consumption.