Windows Vista - http://www.vistaarticles.com
Using Windows low power state
http://www.vistaarticles.com/articles/551/1/Using-Windows-low-power-state
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Published on 05/1/2011
 
The older a PC gets, the longer it takes to start up and shut down.

Using Windows low power state
The older a PC gets, the longer it takes to start up and shut down as Windows launches or stops applications and loads updates. Click the gold power button from the Start menu and Vista saves your current documents and settings before switching to a low power state. This means that when you start the PC up again, the computer doesn’t have to go through that lengthy startup process. A real boon for people who use their PC often.