1. Check Task Manager for high usage
Press Ctrl+Shift+Esc → Processes tab. Sort by CPU then Memory. Identify any process using over 80% — note its name and look it up. Legitimate Windows processes rarely spike to 100% sustained.
2. Disable startup programs
Task Manager → Startup tab. Disable everything you don't need at login. Common culprits: Teams, OneDrive, Spotify, Discord, antivirus updaters. These all compete for RAM at boot.
3. Check available disk space
Open This PC. Your C: drive needs at least 15% free space to run efficiently. Below 10% causes severe slowdowns. Run Disk Cleanup (search in Start menu) and empty Recycle Bin.
4. Run Windows Update
Settings → Windows Update → Check for updates. Pending updates can cause background activity spikes. Install all pending updates and restart.
5. Scan for malware
Open Windows Security → Virus & Threat Protection → Quick Scan. Then run a full scan with Malwarebytes Free (free download from malwarebytes.com). Malware is a top cause of slow performance.
6. Check your RAM
If you have 4GB RAM or less on Windows 10/11, your system will be perpetually slow. Check: Settings → System → About. Upgrading to 8GB or 16GB is often the single best investment for performance.
If your PC is still slow after following all these steps, or if Task Manager shows consistently high usage with no identifiable cause, a technician can run advanced diagnostics to find hardware failures, deep malware infections, or OS corruption.