What is your ambient temperature?
82-83 degrees isn't a dangerous temperature, just not the preferred. This card is going to run hotter than other cards, due to the nature of such a powerful GPU. Also if your ambient temperature is hotter than the average persons than this is going to be a bit warmer than other peoples' 780 Ti DCu II. Listed below are some basic things you can try to help temperatures and airflow inside your case.
Clean out the heatsink, fan, and the entire computer with some compressed-air from a can and use a paint brush to get at the delicate hard-to-reach places. Orient your fans so that the top-back fans are blowing out, and the side-front-bottom fans are blowing in. Clean up any messy cable managment that may be impeding airflow.
Finally, take off the side of the case and blow a house fan into it. If the temperatures drop dramatically, add more fans or replace fans with better models to move more air in and out of the case.