Yeah a GPU will handle well over 70-80 but I feel more comfortable haveing it below 70 not for the safety of the card but for the supper hot ambient air created by the card running so hot in your case...there have been moments on my 4870X2 where the large metal plate on the back of the card is so hot I swear I could cook food on that....So a simple profile mod and my temps are under 60 without much noise...and the card is far more touchable...and case temp far lower.
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