I have my video card settings to turn off the monitor after 5 mins of inactivity. This means the screen blanks 5 mins into a slideshow. It's a bit of a pain to set the video properties to "never" everytime I run a slideshow, so a feature to do this automatically (and restore the originial setting when the slideshow has finished) would be very useful.

My TV card software does it, so it should be possible!