dvd shuts my computer down

[nodeities]

Every time I use either one of my dvd drives to watch a movie, my pc shuts down about 30 seconds after the movie starts.  This happens when I use windows media player or the ati dvd player.  Does anyone have any idea why this would happen 

[Geek-9pm]

Either your Power supply is weak or the DVD Drives are taking too much power.
Have to tried to dis connect  either of the drives?

[Broni]

...or overheating....