When your CPU is running at 100%, your computer becomes slow and unresponsive. Here’s how to diagnose and fix high CPU usage in Windows 11.
Find What’s Using CPU
- Press Ctrl + Shift + Esc (Task Manager)
- Click CPU column to sort by usage
- Identify the process using most CPU
- Note the process name for targeted fixes
Common CPU Hogs
System Interrupts
If “System Interrupts” is high (over 5-10%):
- Usually indicates driver or hardware problem
- Update all drivers
- Check for faulty hardware
WMI Provider Host
WMI causes high CPU when other programs query it poorly:
- Open Event Viewer
- Applications and Services Logs > Microsoft > Windows > WMI-Activity > Operational
- Look for errors indicating the problematic program
- Update or remove that program
SearchIndexer
Windows Search indexing:
Temporary fix:
- Services > Windows Search > Stop
Permanent fix:
- Settings > Privacy & security > Searching Windows
- Adjust indexed locations
- Exclude large folders
Antimalware Service Executable
Windows Defender scanning:
- Open Windows Security
- Virus & threat protection > Manage settings
- Add exclusions for large/known-safe folders
- Schedule scans for idle times
Windows Update
Update checks use CPU:
- Wait for updates to complete
- Check Settings > Windows Update
- Install pending updates
Runtime Broker
If Runtime Broker uses high CPU:
- Settings > Privacy > Background apps
- Turn off apps you don’t need
- Or disable “Let apps run in background”
Quick Fixes
Fix 1: Restart Your Computer
Simple but effective:
- Restart (not just sleep)
- Check CPU usage after restart
- Often clears temporary issues
Fix 2: End Resource-Hungry Processes
- Task Manager > Processes tab
- Right-click high-CPU process
- Select End task
- Note: Some system processes can’t be ended
Fix 3: Disable Startup Programs
Too many startup programs:
- Task Manager > Startup apps tab
- Disable unnecessary programs
- Keep only essentials enabled
- Restart computer
Fix 4: Adjust Power Settings
Power saver can cause issues:
- Control Panel > Power Options
- Select Balanced (not Power saver)
- Or click battery icon and choose balanced
Driver Fixes
Update All Drivers
Outdated drivers cause high CPU:
- Visit laptop/motherboard manufacturer
- Download latest drivers:
- Chipset
- Graphics
- Audio
- Network
- Install and restart
Roll Back Problematic Driver
If high CPU started after driver update:
- Device Manager
- Right-click device > Properties
- Driver tab > Roll Back Driver
Windows Fixes
Run SFC and DISM
Repair corrupted files:
- Command Prompt as Administrator
- Run:
sfc /scannow - Then:
DISM /Online /Cleanup-Image /RestoreHealth - Restart
Windows Update Reset
Stuck updates cause high CPU:
- Command Prompt as Administrator:
net stop wuauserv net stop bits ren C:\Windows\SoftwareDistribution SoftwareDistribution.old net start wuauserv net start bits - Check for updates again
Reset Windows (Last Resort)
- Settings > System > Recovery
- Reset this PC > Keep my files
- Reinstalls Windows, keeping personal files
Malware Scan
Crypto miners and malware peg CPU at 100%:
Signs of Malware
- CPU high even when idle
- Unknown processes running
- Computer hot all the time
- High CPU in browsers without activity
Scan Steps
- Windows Defender full scan
- Download and run Malwarebytes
- Consider offline scan for persistent infections
If a scan finds something, removing it once often is not enough. Our complete virus removal guide shows how to make sure it stays gone.
Advanced Fixes
Perform Clean Boot
Find conflicting software:
- Press Windows + R, type
msconfig - Services tab > Hide all Microsoft services > Disable all
- Startup tab > Open Task Manager > Disable all
- Restart
- If CPU normal, enable items in groups to find culprit
Check for Hardware Issues
High CPU can indicate hardware problems:
- Failing hard drive
- Overheating (thermal throttling)
- Memory issues
Use HWiNFO to monitor temperatures.
Specific Process Fixes
svchost.exe High CPU
Many services run under svchost:
- Task Manager > expand svchost entry
- See which service is using CPU
- Target that specific service
MsMpEng.exe (Defender)
Windows Defender using high CPU:
- Add exclusions for large folders
- Limit scan frequency
- Consider third-party antivirus if persists
wsappx
Windows Store app updates:
- Wait for app updates to complete
- Or disable automatic app updates
- Settings > Apps > Microsoft Store > App updates
CPU Always at 100%? Our Dallas technicians diagnose and fix high CPU usage issues. We identify problematic software and hardware and restore normal performance.
Prevention
- Keep software updated
- Don’t install unnecessary programs
- Use reputable security software
- Monitor CPU temps to prevent overheating
- Restart computer weekly to clear issues
Tried the steps and still stuck?
Tell us what's happening and a DFW technician will get back to you within 30 minutes during business hours. We come to your home or office, same day.