Microsoft declared that Windows 7 will be much more energy efficient than Windows Vista, if both were run on two laptops with the same configuration. Gabriel Aul of the Windows Performance team confirmed that the battery life will be very efficiently used in Windows 7.
Windows 7 ‘parks’ CPU cores that are not needed unlike Vista which makes no such ‘moves’. Windows 7 even stops SATA drives for no activity, powers down USB ports and controllers and even more interesting, it shuts down the wireless radio when there is no Wi-Fi network around. I think this is a very logical move. TechRadar says, “Microsoft has also changed its thinking about the system timer; in Vista this is set to 1ms, in Windows 7 it will be 15ms, which reduces the power draw by 15 per cent.” I guess, the basic idea is “a dollar saved is a dollar earned” in the context of energy efficiency.
All system processes which ran without any apparent reason in the previous versions of Windows are periodically checked for their relevance. Even changes have been made to Windows Media Player which will now cache video in a buffer, “so it can spin down the DVD drive and using less CPU power to deal with DRM and copy protection.” Very smart move. Microsoft thinks this will save a minimum of 11% of the notebook’s battery life.
Overall, if you are thinking that Windows 7 is just another Windows Vista inside, with a different skin, you are wrong. Windows 7 seems to be rather a whole new technology with the Windows logo on it.