This policy setting configures a local override for the configuration of maximum percentage of CPU utilization during scan. This setting can only be set by Group Policy.If you enable this setting the local preference setting will take priority over Group Policy.If you disable or do not configure this setting Group Policy will take priority over the local preference setting.
Policy path:
Windows Components\Windows Defender\Scan 
Scope:
Machine 
Supported on:
At least Windows Server 2012 Windows 8 or Windows RT 
Registry settings:
HKLM\Software\Policies\Microsoft\Windows Defender\Scan!LocalSettingOverrideAvgCPULoadFactor 
Filename:
WindowsDefender.admx 
