1. A method of establishing a power profile of power consuming components of computer system configurations for generating electrical ratings, the method comprising: beginning with a default, limited configuration of a computer system and continuing for a plurality of configurations of the computer system, each configuration including additional power consuming components not included in a previous configuration: measuring, by a power profiling module for a present configuration, power consumption of the computer system; calculating, by the power profiling module in dependence upon the measured power consumption for the present configuration, an estimated power rating for the one or more additional power consuming components not included in the previous configuration; and recording, by the power profiling module in a power profile, estimated power ratings for the one or more additional power consuming components not included in the previous configuration, wherein the number of configurations of the computer system for which power consumption is measured is less than the number of possible configurations of the computer system and wherein the power profiling module comprising one or more module of automated computing machinery.