Abstract: A portable computer is provided in which the consumption of power by the I/O ports of the computer is reduced. The processor of the computer distinguishes port I/O operations that require an actual data transfer from port I/O operations that do not require an actual data transfer. The I/O ports of the computer remain off until an I/O operation involving an actual data transfer at a particular port is required. When an I/O operation which requires an actual data transfer is encountered, then the appropriate port is powered up. In this manner, power consumption by the I/O ports of the computer is significantly reduced. Advantageously, the disclosed technique for reducing power consumption by the I/O ports of the computer is operating system independent. In this manner, the power management feature functions regardless of which particular operating system or application software is installed on the computer.