Don't count on the 65nm chips being less power hungry, that rule
doesn't work the way it used to anymore. They have to do a lot more
development nowadays to get the chips less power hungry than simply
just shrinking it. The rule broke down when they made the transition
from 130nm to 90nm this time.
As an example of all of the extra things they have to do these days, we
can take Intel's experience vs. AMD's experience as a textbook account.
Intel raced to get their transition to 90nm done ahead of AMD and the
others. They were able to do this by simply doing a shrink to 90nm
without adding any new ingredients into their manufacturing process,
such as Silicon-On-Insulator technology. AMD on the other hand
specifically researched new manufacturing technology and added it into
their 90nm transition, in fact, they even added the technology into
their 130nm technology (they wanted to get practice at using it in the
mature previous generation). The result was, Intel's processors all
use more power at 90nm than they did at 130nm (even their Centrinos),
the amount of extra power depends on the Mhz level that each processor
runs at. By contrast, AMD was able to reduce their power consumption by
25% across the board when they transited!
Yousuf Khan