This disclosure is directed to techniques for providing supply power to components of an electronics system, such as components of a networking device. According to these techniques, a power supply system charges a bulk capacitance of a power supply unit when the power supply unit is selectively disabled (e.g., disconnected). In this manner, when the power supply unit is again enabled, the power supply unit may provide supply power to components of the networking device faster in comparison to other techniques. In addition the power supply does not use any input power and therefore does not produce any heat loss while it is disconnected, thus saving otherwise wasted energy.