Yeah that cooler is not very good. Im mining on mine and im seeing 76 c 1000/1474 fan @ 100%
Good thing I have a waterblock for that mofo
I will take back my words. I put some new tim and now im at 66 c @ 70 % fans speed 1.180v 1100/1500. I guess mining is killing that shin etsu tim. I just replaced it about a month ago when I got the card.
Try to adjust the voltage upper than 1220 mv to see for you shelf about the heat problems. I had changed the tim on the card with DC2 cooler, but the improvement wasn't enough as it was with the replacement of the cooler.