At COMPUTEX 2009 Intel told attendees that Windows 7 features better multi-threading, which will improve power consumption and battery life for netbooks and notebooks.
The improvements are because Windows 7′s kernel manages multi-core CPUs better, and locks threads to a particular core rather than the swapping threads around cores. Â Swapping threads meant that older versions of Windows couldn’t enter lower power C-states and also introduced inefficiencies as cores took over data that had already been partially processed by other cores.
Lower power C-states, or tread parking, is supported by Intel Nehalem and AMD Phenom II processors (your motherboard will need to also), so users with the right hardware will see much better power consumption figures.
Source: Bit-tech
