display dimming

i went into system preferences and nothing is set up to dim before screen saver or nothing
and this is a problem when im watching a movie in quicktime it would dim 30 minutes in
any ideas?

I forget exactly what the time difference is but its a built in functionality to dim the screen after a certain amount of time of no mouse/keyboard activity before the screensaver/sleep start. If you increase the time before screen saver then that will give you more time, or if you are watching full screen it doesn't do the dimming