Energy Per Instruction Trends in Intel Microprocessors

Overview

Energy Per Instruction (EPI) is a measure of the amount of energy expended by a microprocessor for each instruction that the microprocessor executes. This paper presents an overview of EPI, explain the factors that affect a microprocessor's EPI, and derive a historical comparison of the trends in EPI over multiple generations of Intel microprocessors. It shows that the recent Intel Pentium M and Intel Core Duo microprocessors achieve significantly lower EPI than what would be expected from a continuation of historical trends.