Inter Core

White Paper
November 2008

Intel® Turbo Boost Technology in Intel® Core™ Microarchitecture (Nehalem) Based Processors

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White Paper

Table of Contents
Table of Contents...............................................................................................................................................................................................3  1.0  Intel® Turbo BoostTechnology ...................................................................................................................................................5  1.1  Overview............................................................................................................................................................................................5  1.2  Dependencies / Algorithm........................................................................................................................................................5  2.0  Operating Frequency........................................................................................................................................................................7  2.1  Problem with Today’s Software Reporting Frequency...........................................................................................7  2.2  Frequency Algorithm...................................................................................................................................................................7  2.3  Determining Maximum Possible Intel® Turbo Boost TechnologyUpside.......................................................8  2.4  Displaying Active Cores..............................................................................................................................................................8  2.5  Displaying Time Spent In C3....................................................................................................................................................8  2.6  DisplayingTime Spent In C6....................................................................................................................................................9  3.0  C-State Definitions......................................................................................................................................................................... 10  3.1 C0........................................................................................................................................................................................................ 10  3.2  C1........................................................................................................................................................................................................ 10  3.3 C3........................................................................................................................................................................................................ 10  3.4 C6........................................................................................................................................................................................................ 10 

White Paper

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Intel® Turbo Boost Technology

1.0 Intel® Turbo Boost Technology
Intel® Core™ Microarchitecture (Nehalem) based processors incorporate a new feature: Intel® Turbo Boost technology. Under some configurations and workloads, Intel® Turbo Boost technology enables higher performance through the availability of increased core frequency. Intel® Turbo Boosttechnology automatically allows processor cores to run faster than the base operating frequency if the processor is operating below rated power, temperature, and current specification limits. Intel® Turbo Boost technology can be engaged with any number of cores or logical processors enabled and active. This results in increased performance of both multi-threaded and single-threaded workloads. It is...