Windows 7 and Windows Vista automatically adds Hibernation option upon install. This will add the same space on your hard disk as of your RAM. For example if you have 2 GB RAM then an extra 2GB will be taken on your hard disk for hibernation. Although this option is great but need space.
You need to open the elevated command prompt to do this
In the start search box type cmd and you will see cmd and right click and on this file and then select Run as administrator, click Yes.
In the elevated command prompt, type powercfg -h off and press Enter.
Now you have disabled the hibernation. Close the cmd
In the elevated command prompt, type powercfg -h on and press Enter. You are done