How to Fix High CPU Usage During Gaming From Antivirus Scanning

What Causes This?

High CPU usage during gaming often happens when your antivirus starts a real-time scan, background scan, or scheduled scan while the game is running. Antivirus tools can aggressively check game files, temporary files, downloads, and memory activity, which competes with the game for CPU time. This is more noticeable on systems with limited CPU headroom, slower drives, or games that constantly load assets in the background.

Common Symptoms

• Sudden frame drops or stutter even though the game usually runs fine
• CPU usage spikes to 90–100% when gaming
• Task Manager shows Windows Security or another antivirus process using a lot of CPU
• Lag gets worse when launching a game, loading a new area, or downloading updates
• Gameplay improves after pausing or disabling antivirus scanning

How to Fix It Manually

1. Confirm that antivirus scanning is the cause

   • Open Task Manager with Ctrl + Shift + Esc.
   • Click More details if needed.
   • On the Processes tab, sort by CPU.
   • Start your game and watch for processes like Antimalware Service Executable, Windows Security, or your third-party antivirus using high CPU.

2. Pause or reschedule active antivirus scans

   • If you use a third-party antivirus, open its dashboard from the system tray.
   • Look for options such as Pause protection, Stop scan, or Game Mode.
   • If there is a scheduled scan set for the time you usually play, move it to a time when the PC is idle, such as overnight.

3. Add your game folder as an antivirus exclusion in Windows Security

   • Press Windows + I to open Settings.
   • Go to Privacy & security > Windows Security > Virus & threat protection.
   • Under Virus & threat protection settings, click Manage settings.
   • Scroll down to Exclusions and click Add or remove exclusions.
   • Click Add an exclusion > Folder.
   • Select your game’s install folder, such as C:\Program Files (x86)\Steam\steamapps\common\YourGame.
   • If needed, also exclude your game launcher folders like Steam, Epic Games, or Battle.net libraries.

4. Exclude temporary game and launcher cache folders if scans keep returning

   • In the same Exclusions area, add folders used by your launcher for downloads or shader caches.
   • Common examples include Steam download cache folders or game-specific cache folders inside AppData.
   • Only exclude folders you recognize and trust.

5. Turn on Game Mode in Windows

   • Press Windows + I and open Gaming > Game Mode.
   • Make sure Game Mode is turned On.
   • This helps Windows reduce background activity while you play.

6. Check for antivirus features designed for gaming

   • Many antivirus apps include Game Mode, Silent Mode, or Do Not Disturb.
   • Enable that feature in your antivirus settings so scans and alerts are reduced during full-screen games.

7. Restart the PC and test again

   • Reboot Windows after changing exclusions or scan schedules.
   • Launch the game and reopen Task Manager to confirm CPU usage is lower and stutter is gone.

Fix It Automatically with Kudu

Kudu can help detect background tasks and system settings that are causing unnecessary CPU load during gaming, including security tools, startup apps, and other performance drains. Instead of hunting through Windows settings one by one, Kudu makes it easier to identify what is eating resources and optimize your PC for smoother gameplay.

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