MBP Late 2011 - fans running even though "mild usage"

Two months or so ago, the warning triangle appeared on the battery icon, telling me to "Service Battery" (According to iStat, my battery health is at 79%) and Ive been told to replace if it ever dips below 80. However, its only two years old, should I really have to replace the battery that early? This might be the cause for the fans being noisy, but still.. if not

Whenever I stream a show, for instance through Netflix, my fans go nuts. Even though I only have that window open, no other app eating ram. Why is the fans experienced such high usage? When I quit the streaming, the fans quiet down after 5-10 minutes.

No, I dont have Applecare.

Help is much appreciated

blueroom said:

Both Microsoft Silverlight (Netflix) and Adobe Flash are resource hungry and will get those fans running.

I had a service battery too on my 3+ year old MBP; unless the battery is swelling I'd wait a wee bit longer before getting it replaced at an Apple store.

Click to expand...

it has gotten very, very sensitive lately. even just starting skype gets it going