Personally, I would not try to grease the card. Maybe it was just my ineptness, but I tried that on one of my old 8800GTS cards, and it wouldn't work at all afterward. As far as temperatures go, it is the highest temperature that it obtains under a load that matters most, and playing a movie is neither at an idle, or a high load. Instead of dismantling the card, I would consider the general cooling of the case...what is the system temp? Can you improve airflow either by cable management or adding fans?