Coincidence but someone else I know recently had similar problems and it was the cable. Are there dodgy cables in circulation or something?
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Thought it would be useful to people in this forum about my experiences installing a second hard drive on my PC - a WD caviar green.
Have spent two weeks tearing my hair out as the drive wouldn't format at first, then it was slow access and then total failure. Was about to send it back but I swapped the SATA cable (which I had bought at the same time as the drive) and everything is great. Apparently, according to various other forums, SATA cable problems are the source of many hard drive problems:
http://users.silenceisdefeat.com/~rwightman/PVRprojects/Blog/Entries/2010/8/3_Recent_PVR_woes.html

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