User Configuration > Policies > Centrify Settings > Mac OS X Settings > Desktop Settings > Set computer idle time for starting screen saver
Select the length of time to wait before starting the screen saver. If you enable this group policy, you can specify the number of minutes to wait while a computer is not in use before starting the screen saver. For example, if you want the screen saver to start after a computer has been idle for 10 minutes, you can set Start screen saver to 10 minutes.
Disabling this policy does not disable the screen saver. To disable the screen saver, enable this policy and set the value to 0.
Although you may specify values greater than 60 minutes, and the screen saver works appropriately, the Macintosh Screen Saver dialog box shows values that are greater than 60 as Never.
Enabling this group policy is the same as selecting when to start the screen saver using the Start screen saver slider in the Desktop & Screen Saver system preference.
Once enabled, this group policy takes effect when users log out and log back in.