Why is my GPU temp. like this?

notice88

Distinguished
Jan 14, 2009
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I'm having trouble with my Video card and I know how to handle it. Sometimes, the temperature reaches 100c then the display will shutdown.. I already remove the dust from the heat sink of the videocard. But its always the same. My video card acted like this just a week a go and I don't change any settings regarding to it.. The fan works just like fan and the heatsink and processor of it has contact.

What am i gonna do? Its working just fine but it always overheating. t.t . Is there any way to maintain its low temp?? removing the cover of the casing doesn't solve it t.t