With emerging use-cases driving the need for higher rack power and density, the adoption of higher bus voltage is becoming a popular choice to enable such server platforms. Higher bus voltages such as 48V is not a new concept within the rack power space as it is already widely used in telecom industry. Over the past few years, various distinct 48V architectures have been proposed and adopted to support on-board DC/DC conversion. This presentation is aimed to provide an overview of the existing 48V architectures and detailed survey of various conversion topology.