A simple checklist for troubleshooting a slow Windows PC

"My computer is slow" is one of the most common requests a support desk receives, and the cause is rarely the first thing you guess. This checklist narrows it down from the cheapest checks to the most invasive ones.

1. Ask a few questions first

• When did it start? Did anything change just before (an update, new software, a new device)?
• Is everything slow, or just one application or website?
• Does a restart help for a while and then it slows down again?

2. Restart, then open Task Manager

Restart first. Many problems are a leftover process or a pending update. Then press Ctrl + Shift + Esc and look at the Processes tab. Sort by CPU, Memory, and Disk. One process pinned near 100 percent usually points to the culprit.

3. Check storage

When the system drive is almost full, Windows slows down because it has no room for temporary files. Open Settings, System, Storage, remove temporary files, and uninstall software nobody uses. Also note whether the machine uses an old hard disk (HDD) or an SSD, because that alone changes what is realistic.

4. Trim startup apps

In Task Manager, open Startup apps and disable high-impact entries that do not need to run at sign-in. This is often the biggest improvement in boot time.

5. Updates and drivers

Install pending Windows updates and check the graphics and chipset drivers. Keep in mind that an update running in the background can make the PC slow temporarily, so give it time before blaming something else.

6. Scan for malware and unwanted extensions

Run a full scan with Windows Security. In the browser, remove extensions you do not recognize. Adware often hides there.

7. Look at the hardware

• Memory constantly near its limit means the machine needs more RAM.
• Replacing an HDD with an SSD is usually the single most effective upgrade for an old computer.
• Dust and heat make the CPU slow itself down. Check temperatures and clean the fans.
• Check the disk health report if the disk is busy at 100 percent without a clear reason.

8. The last resort

If nothing helps, back up the user's files and reset Windows. It is slower for the user than the earlier steps, so save it for when the cheaper checks have failed.

Write it down

Record what you tried and what worked in the ticket. The next time someone reports the same symptom, you will already have the answer.