I like the official catalysts - i'm going to update to the 5.7s tonight after work. I recommend going to
www.tweakguides.com - that guy will tell you everything you could possibly need to know about getting your system running as smoothly and efficiently as possible. he has a whole ati tweak guide in which he holds your hand through the whole clean install process. before i went there i couldn't get battlefield 2 to run at all on my notebook - but after going through his windows xp tweak guide, following his directions for updating motherboard and bios drivers, and following instructions on the ati catalyst tweak guide, the game is running like a dream and my notebook seems to be running more efficiently in general. i highly recommend it...