GPU Usage when idle and temps

Hey guys!

Yesterday I had a problem, it was really hot and I'd just finish playing Gta V and I was just in a skype call when my Radeon HD 7870 from MSI starts spinning up the fans. I open up afterburner and see the usage at high 80s (87 89, around there) even getting to 95! and the temp was at around 53ºC.
My first suspicion was a miner virus, which it seemed like it seeing as AVG detected a trojan, but the problem still stayed. I searched online and decided to try roguekiller and that seemed to fix it.
Now I just finished playing civs and my gpu usage is hopping between 7 and 24 just up and down every second and the temp is staying constant at 41. The only things open are skype and chrome.
Is this normal or should I be worried?

Thanks :)