Windows Defender High CPU Usage

Why this happens and what it looks like

When CPU usage is high at idle, something is running when nothing should. Common culprits are updaters, indexing, telemetry, or a stuck process.

You notice fans ramping and apps taking longer to open. Task Manager reveals which process is busy at idle.

Quick steps to improve performance

1. Review Startup apps and disable non essentials.
2. Clean Temporary files and Windows Update leftovers.
3. Update drivers from your PC or motherboard vendor.
4. Pause cloud sync during heavy work.
5. Reboot and retest, then fine tune.

Related Guides

• Disable Startup Programs
• Clean Junk Files
• Free Up Disk Space

Run a free PC scan with PC-Care.ai to find and fix what is slowing your computer down.

FAQ

What causes this problem in Windows

Common causes include startup load, clutter, outdated drivers, and busy background apps.

Where should I start troubleshooting

Review Startup apps, clean Temporary files, and install updates first.