The initial Sata 1 drives by WD have jumpers on them. Sata II is the jumper free type drive if you review WD's support site and look up any specific model for installation information. One set of instructions for WD Sata 1 models is titled: "How to enable and disable SSC (spread spectrum clocking) on WD Serial ATA hard drives."
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Question: "How to physically install a Serial ATA drive in a computer system." referring to Sata 1 type drives.
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