Due to a continuously increasing power demand of computer–network server equipment, power supply manufacturers are faced with requirements for ac/dc server power supplies with significantly higher power densities. In this paper, circuit technologies and optimization techniques that are suitable for meeting these new power-density requirements are discussed. The focus of the paper is on single-phase, single-output ac/dc power supplies that are used to generate a dc-bus voltage in distributed power systems employed in high-end network servers and telecom systems.