I assume your talking about the GT which i also have.
These cards have a habit of clogging up with dust where it is hard to find, if you open up the card and take the metal plating off you will find the copper block which is some kind of haven for dust, but at the same time blocks airflow and just acts like a blanket (which i might add i have one rapped around me now:super_happy
instead of a cooler.
Clean the dust out and put some new paste on. Mine went from idle 50+ Celsius and up to 96 Celsius load to atm 41 idle and max 72 load