this only happens when you play a game right? it's because your card cannot handle both screens at once while your playing a game.
if this doesnt happen while you are just surfing the net then it proves that ur card being too noob as mentioned above.
in order to farther verify this, change the larger monitor resolution to 1024x768 and play a game, keep the small monitor the same resolution.
lol @witeboy07, when you have no idea what you are talking about, its better to shut up then make a fool outta yourself.