[CUBE] Switch between dual and single

[Tom Davidson]

Disabling one CPU with CHUD  really wont save any noticable power, the 
idling CPU is still clocked.
Even when doing nothing, the chip uses a whole lot of power just 
clocking at 500MHz or whatever.
 The only way to save power would be to put it into deep sleep and 
disable it's clock, but the Apple software
 doesnt allow for it as far as I know. Anyone familiar with low-level 
programming of the Apple Uni-North chip?
It may be possible to write a utility if the chip controls are available 
as register control bits. The reason Apple
may not support this is thermal issues of having one hot CPU next to a 
cool one creating mechanical stress
in the board due to unequal thermal expansion.