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Title: Does not work with a PowerBook unless you purchase the external power supply
Review: Overall the drive works great with any desktop CPU I have used it on, but I purchased it to use with my Powerbook laptop. After talking to Western Digital Tech Support they told me that it will not work with any PowerBook unless you use an external power supply. USB 2.0 specification limits bus power to 500mA. Some notebook manufacturers, including Apple, abide by this specification and provide 500mA to the hard drive. 500mA isn't enough current to get this hard drive operational. So you need the external power supply. Would have been nice if Western Digital had designed their drive to be USB 2.0 compliant.
