I have an nVIDIA GeForce 6200 (AGP) 256Mb graphics card that i would like to overclock. I have had a bit of a browse on how to go about it, but found a mixed opinion of whether its worth doing or not. I'm not interested in buying a new card, but would like to improve this one as much as possible. Is it worth doing to this card, and what type of performance improvement could i expect? if so, how should I go about it?