Originally Posted by
ScottC
Hyperthreading is an old(er) technology. You won't find it on the current Core Duo and Core2duo chips.
Many dual core systems have an option in the bios to disable "multi-core support" or something similar. I'm not sure that it will save any battery life - it might actually cost it, as WhoTF knows what clock or voltage the disabled core will run at, while if you leave both cores running they will be handled by the OS's power management.