Q: I’ve installed Windows Vista on my laptop but I do not see hibernation listed in the Shutdown options. How do I enable this?
A: During Windows Vista installation, setup looks at your current memory and if the system has 4GB or greater, Windows will not enable hibernation by default. Many OEMs work around this by enabling hibernation in their pre-install images.

For enterprise and home users, you can use the following procedure to enable hibernation:

  1. Log on on to Vista with an Administrator account.
  2. Click Start, type cmd in the Start Search text box.
  3. Right-click cmd.exe, click Run as Administrator, and then click Continue.
  4. Now you are ready to enable hibernation. Type in the following without the quotes “powercfg –h on” and press enter. 

This will enable hibernation and unlike Windows XP you will not need to limit the RAM to under 4GB by using msconfig to enable hibernation in Windows Vista.
-David Winkler