I have yet to see how much the difference can be in battery savings through this setting, but I’ll take even the minimum savings I can get.
Now, to make sure I can stop using Google Chrome and switch to Internet Explorer 9 when using my notebook on battery.
Windows 7 contains tons of other power saving improvements which include new display brightness settings, video playback, AHCI Link Power Management, System cooling policy and more. This allows different operating system features to work together to save as much battery life as possible. Since Windows 7 also uses fewer CPU cycles and memory, compared to its predecessor Windows Vista, that also helps in making it more battery efficient than what was possible before.