COMPUTER SYSTEM AND METHOD PROVIDING BOTH MAIN AND AUXILIARY POWER OVER A SINGLE POWER BUS

A computer system includes power-consuming components, a power supply providing power to the power-consuming components, a single power bus extending from the power supply to each of the system components, and a service processor in communication with the components and the power supply. The service processor sends a turn on signal to the power supply in response to detecting activity of the power-consuming components and sends a sleep mode signal to the power supply in response to detecting inactivity of the power-consuming components. The power supply supplies power to the single power bus at a first voltage in response to receiving the turn on signal and supplies power to the single power bus at a second voltage in response to receiving the sleep mode signal, wherein the first voltage is greater than the second voltage.