My TB 800 is overclocked to 1000 and it is running between 44 and 47c, using a FOP38 (very Noisy fan though I think that I can get use to it), and cheep grease. I first tried that stupid Super ORB and it ran between 47 and 55c. Without grease it ran at over 63c.
I still havent lapped the heat sink yet, and I am not sure if the artic silver will help much but I am also going to try it.