I have relatively good airflow in my system (140mm intake fan, 120mm exhaust, tons of ventilation).
My problem is that my STRIX 980 doesn't stay under 65 degrees at idle. So every minute or so it peaks above 65, the fans kick in (albeit at low RPM) then ramp back down until it's at about 50 degrees, then stop. This then repeats, over and over and over, while I'm using the PC for browsing, video watching and so on.
The only time the "0db technology" actually works is if the screen is in standby (idle). This allows it to stay under 65 degrees with no fan. But even running Aero makes it slowly creep over 65 and make the fans run.
Granted, I run my desktop 2560x1440 at 144 Hz - I haven't tested it at 1080p. But I wonder if my passive cooling is optimal or if anyone else is experiencing this. It's supposed to stay under 65 during "light gaming" or video watching yet mine can't just running the desktop.
Otherwise the card is a good performer (120% power, +170 core, +400 memory for me) and heavy gaming is in the mid to high 70s, so load temps are good.