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This article proposes a new structure of the server power supply for the dc power distribution system. The proposed structure consists of a boost converter for the preregulating stage and an asymmetric LLC (ALLC) converter for the standby stage. The switches of two converters are integrated to reduce the number of components. To regulate the output voltages of both stages tightly, a hybrid control of pulsewidth modulation (PWM) and pulse frequency modulation (PFM) is used. The proposed structure features zero-voltage-switching (ZVS) turn-on of switches resulting in a small switching loss. In addition, the snubber is not required in the proposed structure. As a result, higher efficiency than the conventional structure can be achieved. The feasibility of the proposed structure is confirmed with 260–380 $V_{\text{dc}}$ input, 400 $V_{\text{dc}}$/500 W (boost converter), and 12 $V_{\text{dc}}$/ 25.2 W (ALLC converter) output prototype.