Ah, I did consider the HD when the fan made it's sick noises, and haven't moved it around very rough since...I would like the math on it, although I am unsure if that will deviate from the PB list's topic... >>> because of the fact that the fan is further from my ears. To an >>> extent >>> I suppose this behavior can be caused by the momentum the fan has >>> built up, and changing the direction may be like trying to turn a >>> spinning gyroscope around. > >> I think that's exactly what's happening. Now, imagine what the same >> movement does to your hard drive! I always move my PB slowly and >> evenly >> if I have to move it while running. > > Constant angular velocity anybody? :) Fastest way to destroy a wear > out the BBs in an HD is by exactly the method you described. I do not > suppose you would like the math on that?