Your card temp is fine, I was worried about it as well so I emailed BFG this is wht I got back :
Thank you for your request. Your temperature reading is normal.
Cards idle around 53c on well cooled systems, under extreme loads they can peak as high as 90-92c. Normal use in games should...
I just got this card yesterday, I noticed the 10 degree jump in temp using the 71.84 so I reverted back to 66.93. But I had no problems running anything with the 71.84 asides from the temps. Can anyone suggest a good aftermarket cooler for the BFG 6800GT OC as the stock cooler bites!!