This external enclosure is using USB 2.0 and is backward compatible with USB 1.1. Most Pentium II, Pentium III and early Pentium IV laptops and computers have USB 1.1. It can be powered by USB 2.0. Some USB 1.1 ports do not have power and you have to use the keyboard connector to draw power(cable is provided). In most cases you can use both cables to draw enough power to run this drive properly especially when using it to write cdroms or dvdroms.
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