Editing amd/frequency behavior

{{amd title|Frequency Behavior}}
The '''Frequency Behavior of AMD's CPUs''' is complex and is governed by multiple mechanisms that perform [[dynamic frequency scaling]] based on the available headroom.

==Overview ==
AMD has implemented a number of mechanisms into their architectures to extract additional performance through higher frequency whenever the power and thermal budgets allow.

* {{amd|Cool'n'Quiet}} - Introduced with {{amd|K8|l=arch}} in 2003
* {{amd|Turbo Core}} - Introduced with {{amd|K10|l=arch}}(Thuban) in 2010
* {{amd|Precision Boost}} - Introduced with {{amd|Zen|l=arch}} in 2017
** {{amd|Precision Boost 2}} - Introduced with Zen-based Mobile in 2017
** {{amd|Precision Boost Overdrive}} - Introduced with {{amd|Zen+|l=arch}}-based Workstations in 2018
* {{amd|eXtended Frequency Range}} (XFR) - Introduced with {{amd|Zen|l=arch}} in 2017
** {{amd|eXtended Frequency Range 2}} (XFR 2) - Introduced with {{amd|Zen+|l=arch}} in 2018
* {{amd|Mobile eXtended Frequency Range}} (mXFR) - Introduced with Zen-based Mobile in 2017

Under Precision Boost, the turbo was defined per core. for AMD's Ryzen brand (i.e. {{amd|Ryzen 3}}, {{amd|Ryzen 5}}, and {{amd|Ryzen 7}}, the maximum turbo frequency is govern by three parameters: ''All Boost'', ''Max Turbo'', and ''XFR Boost''. With only one to two active cores, the processors can hit the ''Max Turbo''. However, anything in excess of two active cores, the processor drops to an ''All Boost'' frequency. For {{amd|Threadripper}}, the ''Max Turbo'' was defined for 4 active cores or less and for AMD's {{amd|EPYC}} brand, the ''Max Turbo'' is defined for 12 or less active cores.

With the introduction of {{amd|Precision Boost 2}}, the per-core definition was eliminated. Instead, the processor will automatically allow turbo for as many cores as the power budget allows.

== See also ==
* Intel's {{intel|Frequency Behavior}}

[[Category:power management mechanisms by amd]]