A scan reads files and may unpack archives or inspect running activity, so temporary CPU, disk, memory, and power use is normal. The effect is usually greatest during a Full scan, on a mechanical disk, or while another disk-heavy task is running.
Reduce the impact
- Use a routine or Quick scan for regular checks and a Full scan when the risk justifies it.
- Schedule long scans for a time when the computer is on but not needed for demanding work.
- Avoid running backups, large installations, another antivirus scan, or heavy file transfers at the same time.
- Keep a laptop connected to power and make sure the Windows drive has free space.
Use exclusions cautiously
Do not exclude a broad folder merely to make a scan faster. Exclude an exact trusted object only after verification, because the scanner will not inspect excluded content in the future. Large archives or backup sets are safer to scan during a scheduled Custom scan than to exclude permanently.
If the PC remains slow
Check whether the scan actually finished, restart Windows, and compare usage when no scan or update is active. Send Support the scan type, duration, affected process, storage type, and application log if high resource use continues.