I have a notebook computer, Averatec model number 6240, that is loud like a lawnmower. The fan has already been replaced three times (at no cost to me, under the store's maintenance agreement) and now it's doing it for the fourth time! Only a few months after the last repair, it's doing it again. I'm thinking ahead, after the maintenance agreement runs out, and this one part has been replaced several more times, I'll have to learn how to fix it myself. Are all notebook computer fans interchangable, or do they depend on the model? Can I get a more reliable but equivalent brand for this part? Does anyone have step-by-step instructions for taking a notebook computer apart and putting it back together again? Thanks for any advice.