Windows 10: Set Windows Defender Antivirus Max CPU Usage for a Scan in Windows 10

How to: Set Windows Defender Antivirus Max CPU Usage for a Scan in Windows 10

How to Change Windows Defender Antivirus Maximum CPU Usage for a Scan in Windows 10


Windows Defender Antivirus.

Windows Defender Antivirus helps protect your PC against malware (malicious software) like viruses, spyware, and other potentially unwanted software. Malware can infect your PC without your knowledge: it might install itself from an email message, when you connect to the Internet, or when you install certain apps using a USB flash drive, CD, DVD, or other removable media. Some malware can also be programmed to run at unexpected times, not only when it's installed.

Windows Defender Antivirus has a maximum 50 percentage CPU usage for a scan by default in Windows 10. If you like, you can specify a percentage of CPU usage you want Windows Defender Antivirus to not exceed.

See also: Configure Windows Defender Antivirus scanning options | Microsoft Docs

This tutorial will show you how to specify the maximum percentage CPU usage allowed for a scan by Windows Defender Antivirus in Windows 10.

You must be signed in as an administrator to specify maximum percentage CPU usage for a scan by Windows Defender Antivirus.



Contents

• Option One: To See Current Maximum CPU Usage for Scan by Windows Defender Antivirus
• Option Two: To Specify Maximum CPU Usage for Scan by Windows Defender Antivirus in PowerShell
• Option Three: To Specify Maximum CPU Usage for Scan by Windows Defender Antivirus in Local Group Policy Editor
• Option Four: To Specify Maximum CPU Usage for Scan by Windows Defender Antivirus using a REG file for Local Group Policy

OPTION ONE [/i] To See Current Maximum CPU Usage for Scan by Windows Defender Antivirus
1 Open an elevated PowerShell.

2 Copy and paste the command below into the elevated PowerShell, and press Enter. (see screenshot below)
Get-MpPreference | select ScanAvgCPULoadFactor
3 You will now see the ScanAvgCPULoadFactor value (ex: "50") for the current maximum percentage CPU usage for a scan.

4 You can now close the elevated PowerShell window if you like.









OPTION TWO [/i] To Specify Maximum CPU Usage for Scan by Windows Defender Antivirus in PowerShell
This option will set the AvgCPULoadFactor DWORD value in the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender\Scan key in Registry Editor.


1 Open an elevated PowerShell.

2 Type the command below into the elevated PowerShell, and press Enter. (see screenshot below)
Set-MpPreference -ScanAvgCPULoadFactor <percentage>

Substitute <percentage> in the command above with a value of 5 to 100 for the maximum CPU usage you want to specify.

Setting a value of 0 will disable CPU throttling for Windows Defender Antivirus allowing Windows Defender Antivirus to use as much CPU as it wants.

50 is the default value.

For example: Set-MpPreference -ScanAvgCPULoadFactor 50



3 You can now close the elevated PowerShell window if you like.









OPTION THREE [/i] To Specify Maximum CPU Usage for Scan by Windows Defender Antivirus in Local Group Policy Editor
The Local Group Policy Editor is only available in the Windows 10 Pro, Enterprise, and Education editions.

If the policy in this option is enabled to specify, it will override Option Two.

All editions can use Option Two or Option Four.


1 Open the Local Group Policy Editor.

2 In the left pane of Local Group Policy Editor, navigate to the location below. (see screenshot below)
Computer Configuration/Administrative Templates/Windows Components/Windows Defender Antivirus/Scan




3 In the right pane of Scan in Local Group Policy Editor, double click/tap on the Specify the maximum percentage of CPU utilization during a scan policy to edit it. (see screenshot above)

4 Do step 5 (specify) or step 6 (undo) below for what you would like to do.


5. To Enable Policy to Specify Maximum CPU Usage for Scan by Windows Defender Antivirus
A) Select (dot) Enabled. (see screenshot below)

B) Under Options, type a value of 5 to 100 for the maximum CPU usage you want to specify, click/tap on OK, and go to step 7 below.

Setting a value of 0 will disable CPU throttling for Windows Defender Antivirus allowing Windows Defender Antivirus to use as much CPU as it wants.

50 is the default value.


6. To Undo Policy to Not Specify Maximum CPU Usage for Scan by Windows Defender Antivirus
A) Select (dot) Not Configured or Disabled, click/tap on OK, and go to step 7 below. (see screenshot below)

Not Configured is the default setting.




7 When finished, you can close the Local Group Policy Editor if you like.





OPTION FOUR [/i] To Specify Maximum CPU Usage for Scan by Windows Defender Antivirus using a REG file for Local Group Policy
The option is for the same policy as Option Three.

If the policy in this option is enabled to specify, it will override Option Two.


1 Press the Win + R keys to open the Run dialog, type regedit into Run, and click/tap on OK to open Registry Editor.

2 Navigate to the key below in the left pane of Registry Editor. (see screenshot below)
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender\Scan

If you do not have a Scan key, then right click on the Windows Defender key, click/tap on New, click/tap on Key, type Scan for the name, and press Enter.





3 Do step 4 (specify) or step 5 (undo) below for what you would like to do.


4. To Enable Policy to Specify Maximum CPU Usage for Scan by Windows Defender Antivirus
A) In the right pane of the Scan key, double click/tap on the AvgCPULoadFactor DWORD value to modify it. (see screenshot below step 2)

If you do not have a AvgCPULoadFactor DWORD, then right click on an empty area in the right pane of the Scan key, click/tap on New, click/tap on DWORD (32-bit) Value, type AvgCPULoadFactor for the name, and press Enter.


B) Select (dot) Decimal, type a value of 5 to 100 for the maximum CPU usage you want to specify, click/tap on OK, and go to step 6. (see screenshot below)

Setting a value of 0 will disable CPU throttling for Windows Defender Antivirus allowing Windows Defender Antivirus to use as much CPU as it wants.

50 is the default value.






5. To Undo Policy to Not Specify Maximum CPU Usage for Scan by Windows Defender Antivirus
A) In the right pane of the Scan key, right click on the AvgCPULoadFactor DWORD value, and click/tap on Delete. (see screenshot below step 2)

B) Click/tap on Yes to confirm, and go to step 6. (see screenshot below)




6 You can now close Registry Editor if you like.

That's it,
Shawn


Related Tutorials

• How to Set CPU Process Priority for Applications in Windows 10
• How to Turn On or Off Windows Defender Antivirus in Windows 10
• How to Turn On or Off Periodic Scanning with Windows Defender Antivirus in Windows 10
• How to Manually Scan Files, Folders, and Drives with Windows Defender Antivirus in Windows 10
• How to Schedule a Scan in Windows Defender Antivirus in Windows 10
• How to Add or Remove Scan with Windows Defender Context Menu in Windows 10
• How to Add or Remove Windows Defender Antivirus context menu in Windows 10
• How to Enable or Disable Scan Archive Files by Windows Defender in Windows 10
• Enable or Disable Scan Mapped Network Drives with Windows Defender in Windows 10
• Enable or Disable Scan Removable Drives during Windows Defender Full Scan in Windows 10
• How to Specify Scheduled Scan Type for Windows Defender Antivirus in Windows 10

:)

 

Windows defender advanced scan extreme cpu overload

I routinely do Windows defender advanced scans. Up until about 2 weeks ago, that is.

All of a sudden the scan was completely maxing out my cpu. I wouldn't say it crashed the computer, but if I tried to do the simplest task while it was running, it rendered the machine unusable due to the draining of resources. Not to mention the scan would disappear, but was still running in the background. The only thing I could do at that point was to wait until it was done scanning, or shut down the unit

I found this thread that's about a year old, followed some of the suggestions, but nothing really helps.

I have no problem with the Quick scan.

High CPU usage when Windows Defender perform a Full Scan in Windows 10 - Microsoft Community

Windows Defender is my only virus protection, so there is nothing to create a conflict.

I put my defender installer folders in the excluded list. I changed my power settings from High Performance to Balanced.

I ran chkdsk /scan, sfc /scannow, dism /online /cleanup-image /restorehealth, and a Memory diagnostic. All normal.

Finally, I did a fresh install.

Is anybody else experiencing this?

 

Windows 10 Defender Full Virus Scan- CPU Usage 100%

High CPU usage has been encountered before: this thread (older) refers to dealing with a corrupt database file, but it's a bit long.
High CPU usage from Windows Defender

There are other such threads if you search for (e.g.)
Defender high cpu usage





In the past, sometimes it's proved necessary to exclude a folder:
High CPU usage from Windows Defender
(same thread)

 

Windows Defender full or custom scan maxes cpu

Hello!

I've been having issues with Windows Defender on Windows 10 for a while now. It started sometime during the summer, though I can't pinpoint the exact date. When I run a full or custom scan, Antimalware Service Executable will quickly start jumping up to
100% cpu and it makes my computer basically unusable for the duration of the scan. It's not a constant 100%, but while it does go up and down it spends a lot of time at or near 100%. It doesn't matter what drive I scan, this issue crops up a few minutes in.
The automatic scheduled scans presumably work alright, since I've never actually noticed them happening.

It's not an issue with background processes, because when Defender is the only thing running it will just hog more %. The highest I've seen it go is 96% cpu for Defender alone. Windows Defender is my only antivirus, so it's not a conflict either.

I've tried googling for solutions and haven't really found anything helpful. I added an exception for MsMpEng.exe, but that did nothing. I can't set an affinity for this process, though some posts suggest that might be normal. I've updated Windows and everything
is the most current version available.

I'd really appreciate any suggestions for resolving this. I need to be able to scan my whole PC, not just a quick or scheduled scan.

 

Defender showing high cpu usage

How long have you been using Windows Defender? Is this your first attempt at a full scan?



I recommend you run a full scan on a new Win 10 computer and from then on suggest you run an occasional quick scan. In fact, Windows Defender automatically runs a Quick Scan every couple of weeks without me telling it to do so. Been using it over
a year since I bought the computer - no malware issues either.



This issue may possibly
be caused by remnants of a long ago removed antivirus program such as a trial version of McAfee or Norton. Suggest run removal tools for any AV program that was ever on the computer. List of
anti-malware product removal tools



This also may be a malware issue - suggest you run two or more of the following scanners: List
of Malware Removal Tools



Any new programs just added that could be slowing down the scan?



REPOSTING



If the issue continues you may want to follow the steps in Problems
starting Windows Defender in Windows 8/8.1/10



And see Configure
Windows Defender in Windows 8, 8.1 and 10 Good information but ignore the ads.



You might also want to review http://www.howtogeek.com/220232/how-to-use-the-built-in-windows-defender-antivirus-on-windows-10/ Good
article but ignore the ads!

If you can't get this problem resolved suggest you post back in this thread and provide additional information.



Alternatively - - -



You may prefer to install a third party antimalware program (which should disable Windows Defender).



There are a number of viable free and paid options available – take your pick…

Choosing an Anti-Virus Program



Is Windows Defender The Best For Windows 10?
Good article but ignore the ads.



http://windows.microsoft.com/en-US/windows/antivirus-partners#AVtabs=win10



And - - -



You may want to seek premium support (that means it’s probably not going to be free) from Microsoft at
https://support.microsoft.com/en-us



Regards…



Top 10 Ways PUPs Sneak Onto Your Computer. And How To Avoid Them. | Emsisoft | Security Blog

 

Windows Defender CPU Usage

Hi,

Windows Security Essentials and Windows Defender are different programs that has different settings. On Windows Defender, you cannot limit its CPU usage during scanning.

Please check this
link for more information about Windows Defender.

Thank you.