A less serious issue has been found in certain revisions of Western Digital's popular Green Power series. In fact, the issue is less a bug than a feature that doesn't play well with certain computing environments ...
The problem is this: The Green Power is designed and marketed as a "green" drive, where power efficiency is the primary engineering concern. As part of this concern, the drive is designed to unload the read/write heads after approximately 8 seconds of inactivity. That in itself is not a bad thing ... However, certain software (notably, SpeedFan and some distributions of Linux) can cause issues because they access the drive regularly every 10 seconds or every minute or so. This causes a cycle of rapid loading and unloading that is stressful to the drive  far more stressful than "ordinary" use in which the drive is either working steadily or completely idle.
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