If you have a newer drive or other device that only includes the "SATA" power input, but your computer's power supply only has the solves the problem.
Plug the 4-pin connector into the power supply output cable and the other (SATA) end into your drive.
Adaptor has male 4-pin connector and female SATA connector.
(Not to be confused with the opposite adaptor which allows newer type SATA power connections to be used with older 4-pin-only drives.)
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