PPC 970Fx not ready for laptop prime time

According to IBM's documentation, the PPC970Fx is supposed to have a consumption of 20W at a speed of 2GHz.
However, the reality is different. The monitoring utilities of the xServe G5 log the processor's consumption in realtime. In idle mode, the consumption is a mere 15W. But under full load, it peaks at 44W.
A Powerbook equipped with this processor would approximately run out of battery power in an hour, with fans blowing all the time.
We shall wait for a less power hungry revision...