I've found that the difference between
OC and not
OC is negligable for this card, when I had one, it seemes so weak that is generally maintains excellent thermal levels with no fan on it whatsoever!
PC Gamer just moved the 9800Pro to the Entry Level gaming
pc, with the way my 9800 has been on the verge in performance, I think they're right. If theres anything a fan will do for ya, it might increase the life of the card by a few months or something.