I have them around 75 degrees, runs really stable +- 775 kh/s.
~ Luc
Can you share your setup ? i have 3 sapphire 280x dual-x get about 705mhash at 50,66,69C. Im waiting for my risers to split my cards. With current setup, they will run at around 50C each. Then i can tune them for more hashes.