Patent ID: 8037330

Claim:
A power supply system for a server, the power supply system comprising: a first power supply unit in communication with an output, the first power supply unit adapted to activate if a load of the server connected to the power supply system is below a predetermined level, and adapted to deactivate if the load is above the predetermined level, wherein the first power supply unit is adapted to have a high efficiency at a light load; a first variable slope circuit adapted to receive information about the load applied to the first power supply unit and to deactivate the first power supply unit if the load is above the predetermined level; a second power supply unit in communication with the output, the second power supply unit adapted to activate if the load is above the predetermined level, and adapted to deactivate if the load is below the predetermined level, wherein the second power supply unit is adapted to have the high efficiency at a high load, wherein the first power supply unit and the second power supply unit are connected in a redundant mode configuration; and a second variable slope circuit connected to the first variable slope circuit, the second variable slope circuit adapted to receive information about the load applied to the second power supply unit and to deactivate the second power supply unit if the load is below the predetermined level.