3 ways to limit Windows Defender CPU usage in Windows 10
Is the Windows Defender Service using high CPU at all times?
If you have real-time protection turned on, Windows Defender will perform a background scan and this can cause high CPU usage.
To prevent Windows Defender from using your CPU too much, you can use the following methods to limit the use of Windows Defender CPU in Windows 10.
Restrict Windows Defender CPU usage through PowerShell
1. Open Windows PowerShell as an administrator and issue the following command. It will display the current maximum CPU usage limit for Windows Defender.
Get-MpPreference | select ScanAvgCPULoadFactor
2. When you need to reduce CPU usage, type the following command and press Enter
. Windows Defender will not use more than 30% of the CPU.
Set-MpPreference -ScanAvgCPULoadFactor 30
Limit Windows Defender CPU usage through Group Policy
1. Open Local Group Policy Editor and browse to:
Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus > Scan
On the right, double-click the policy Specify the maximum percentage of CPU utilization during a scan .
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2. Select the Enabled option and limit the Windows Defender's CPU usage to 30% or whatever percentage you prefer. Click Apply and then click OK.
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3. Restart the computer to apply the changes.
Restrict Windows Defender CPU usage through Registry Editor
1. Open Registry Editor and navigate to:
HKEY_LOCAL_MACHINESOFTWAREPoliciesMicrosoftWindows Defender
Right-click on the Windows Defender key and select New> Key . Name it Scan.
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2. Next, right-click the newly created Scan sub-key and select New> DWORD (32-bit) Value .
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3. Name DWORD AvgCPULoadFactor, then double-click it to specify the maximum CPU percentage for Windows Defender.
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4. Close Registry Editor. Restart the computer and check if Windows Defender is still using the CPU at a high level.
You should read it
- Instructions for using Windows Defender
- How to turn off the Windows Defender Summary notification on Windows 10
- How to add exceptions in Windows Defender on Windows 10
- How to fix errors cannot open Windows Defender on Windows 7/8/10
- Use Windows Defender with Command Prompt on Windows 10
- How to kill viruses with Windows Defender Offline on Windows 10 Creators
- How to use Windows Defender to scan programs that do not want PUP?
- Instructions to turn off Windows Defender completely on Windows 10
- Add the 'Scan with Windows Defender' command to the right-click menu in Windows 8
- How to Turn Off Windows Defender in Windows 10
- Shadow Defender - Download Shadow Defender here
- How to protect files from being mistakenly deleted by Windows Defender
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