Certain aspects of a system for controlling power for a network interface controller device may comprise a precision voltage comparator that may instantaneously detect ramp up of a main voltage corresponding to a main voltage source in order to control the network interface controller device. A power monitor may detect when a threshold voltage of the main voltage is reached during the ramp up. A main voltage source switch and an auxiliary voltage source switch may switch an output from an auxiliary voltage to the main voltage source without the switches being simultaneously on. The power monitor may determine whether the main voltage is ramping up in excess of a determined rate and if so, may decrease a rate at which the main voltage ramps up. A current limiter and/or the power monitor may monitor and limit an inrush current caused during main voltage ramp up.