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Difference between revisions of "amd/frequency behavior"
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* {{amd|Precision Boost}} - Introduced with {{amd|Zen|l=arch}} in 2017
 
* {{amd|Precision Boost}} - Introduced with {{amd|Zen|l=arch}} in 2017
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** {{amd|Precision Boost 2}} - Introduced with Zen-based Mobile in 2017
 
* {{amd|eXtended Frequency Range}} (XFR) - Introduced with {{amd|Zen|l=arch}} in 2017
 
* {{amd|eXtended Frequency Range}} (XFR) - Introduced with {{amd|Zen|l=arch}} in 2017
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* {{amd|Mobile eXtended Frequency Range}} (mXFR) - Introduced with Zen-based Mobile in 2017
  
 
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'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.

Revision as of 11:48, 27 October 2017

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.

For AMD's Ryzen brand (i.e. Ryzen 3, Ryzen 5, and 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's EPYC brand, the Max Turbo is defined for 12 or less active cores as opposed to two like Ryzen.

See also