A method for controlling power consumption while maximizing processor performance. The method includes, for a time interval of operation in a first operational state, determining an amount of power consumed during by one or more cores of a processor, calculating, a power error based on the amount of power consumed in the time interval, obtaining a power error term for the interval by adding the power error to a power error term from a previous time interval, and comparing the power error term to at least a first error threshold. If the power error term is outside a range defined at least in part by the first error threshold, the method exits the first operational state and enters a second operational state. If the power error term is within the range defined at least in part by the first error threshold, operation continues in the first operational state.