I recently installed a GTX 680 in my Mac Pro to replace my aging HD 5870. I am happy with the results so far but have a couple of questions. I read in another post that the maximum power supported by the Mac Pro for video cards (powered by two 6-pin cables) is 225 W. From what I can tell, this card has a TDP of 195 W, so I should be safe. However, I've noticed that the card comes with software from the manufacturer (ASUS) that allows to me to apply some basic overclocking. My main questions are: 1) Is it generally safe to overclock the card, or can this greatly reduce the life expectancy of the card? 2) Could playing with these values cause the power consumption of the card to go above 195 W (or 225 W for that matter) and cause damage to the logic board? I would appreciate any advice you could give!