How do i prevent monitor power off...

...when running a fullscreen application?

I'm using Media Player Classic, and my monitor shuts off after 15mins when watching a film.
I WANT it to turn off after 15mins, but not when i'm doing something! It never used to until i just re-formatted and installed Vista 64

Thanks

Generally speaking, if you are busy with something, then the screen will not switch off after 15 minutes (or whatever other timeout you have specified). But the computer eventually registers an "idle" state when you are watching a video or dvd.

In Media Player, if you go to "Options", "Player", you can turn off the "Allow screen saver during playback" to prevent the screen saver from getting in the way of you movies that you are watching. I've not used Media Player Classic for over 2 years now (it just doesn't cut it), but you need to check it's settings also. Perhaps a similar option is allowing the screen saver/power management during playback.

Other than that, I'd actually recommend you switch back to Windows Media Player...