SARANA118 The USB 3.0 standard adds four more wires for data transmission. The technical links at the end of the article contain lots of detail if you'd like to learn more. A USB 3.0 cable can supply up to 900 milliamps of power. On the power wires, the computer can supply up to 500 milliamps of power at 5 volts.|He was Replaced by Sean Pierson