Why Is My Computer Suddenly Slow?

A backup is the first diagnostic dependency.

Confirm a recoverable copy before uninstalling, resetting, repairing a drive, or reinstalling the operating system. Do not let urgency remove the recovery path.

“Slow” needs a reproducible observation.

Record whether startup, one application, network access, disk access, or the entire interface changed, and note the update, installation, or event that preceded it.

CPU, memory, storage, startup, and thermal patterns narrow the path.

Follow current Microsoft or Apple guidance. High utilization is evidence to investigate, not automatic proof that a component is defective.

Malware and hardware are possible, not default conclusions.

Use platform security scans, check free space and updates, and compare a clean restart. Seek repair when crashes, drive warnings, overheating, or data errors persist.