guys, i'm havin a prob with my sapphire hd4830. sometimes, randomly, the gc will crash, and my lcd will say no signal detected. and whenever it crashes, the gc fan will spin at max speed, and there's a light coming from an led on the backplate of the gc (it's labelled "over temp protect"). the led usually just blinks once or twice during startup, but during crashes, it will be switched on constantly. can u guys help me out? and it's not becos of overload or anything, cos it happens even when i'm just surfing the net. gc temps and load are normal. thanks!