As a quick tip...CCC had some issues controlling fan speeds with a few different 4xxx and 5xxx series radeons. I noticed this when mining and decided to manually set fan speeds through catalyst control center / amd overdrive enabled. Brought temps down from 80c to 58c, and fan was only at 50%.
Also, HWMonitor from the company CPUid can show GPU temp too. Its not good for the cards to run around 90-105c.