I can read 1000 words per minute, but can only type about 35 wpm. Therefore, to avoid my brain getting too far ahead of my fingers, I throttle down my intelligence to approximately 3% capacity.

Err, what was the question?     Ahh, yes, MS gives this explanation:

Target Frame Rate

In a movie theater, the film generally runs past the projector's lens at a rate of 24 frames per second. At this speed, the human eye cannot detect the fact that the film is actually a series of rapidly changing still pictures. Like a movie, animated graphics are rendered on a computer screen one frame at a time. This happens at a high frame rate so it seems like a constant picture.

For some computers, it may be advantageous to limit the target frame rate. By limiting the upper end of the frame rate, the computer doesn't spend any more resources than it requires to render the selected frame rate. Resources not used to increase the frame rate beyond that setting can be used for other tasks like rendering clouds or drawing scenery in the distance. Experiment to find the frame rate that works best for you.

http://www.microsoft.com/games/flightsimulator/fs2004_learningcenter_display_set...