Editing Power management (section)

==Processor level techniques==
The power management for microprocessors can be done over the whole processor, or in specific components, such as cache memory and main memory.

With [[dynamic voltage scaling]] and [[dynamic frequency scaling]], the [[CPU core voltage]], [[clock rate]], or both, can be altered to decrease power consumption at the price of potentially lower performance.  This is sometimes done in real time to optimize the power-performance tradeoff.

Examples:
* AMD [[Cool'n'Quiet]]
* AMD [[PowerNow!]]<ref>{{Cite web
|url=https://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_8796_12353,00.html
|title      = AMD PowerNow! Technology with optimized power management
|publisher  = AMD
|access-date = 2009-04-23
}}</ref>
* IBM [[EnergyScale]]<ref>{{Cite web
|url=http://www.ibm.com/systems/power/hardware/whitepapers/energyscale.html
|title      = IBM EnergyScale for POWER6 Processor-Based Systems
|publisher  = IBM
|access-date = 2009-04-23
}}</ref>
* Intel [[SpeedStep]]
* Transmeta [[LongRun]] and LongRun2
* VIA [[LongHaul]] (PowerSaver)

Additionally, processors can selectively power off internal circuitry ([[power gating]]). For example:
* Newer [[Intel Core]] processors support ultra-fine power control over the functional units within the processors.
* AMD [[CoolCore]] technology get more efficient performance by dynamically activating or turning off parts of the processor.<ref>{{Cite web
|url=https://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_9485_9487%5E10272,00.html
|title      = AMD Cool'n'Quiet Technology Overview
|publisher  = AMD
|access-date = 2009-04-23
}}</ref>

[[Intel VRT]] technology split the chip into a 3.3V I/O section and a 2.9V core section.  The lower core voltage reduces power consumption.

===Heterogeneous computing===
[[ARM Holdings|ARM]]'s [[big.LITTLE]] architecture can migrate processes between faster "big" cores and more power efficient "LITTLE" cores.