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Slow PC

A computer that is slow to start, slow to open programs, or freezes during normal work.

Windows 10 / Windows 11about 3 min read

Symptoms

  • Long start-up or sign-in time.
  • Programs take a long time to open, or the mouse lags.
  • Fan constantly loud, or the laptop gets very hot.
  • "Not responding" windows, or the disk light stays on.

Before you start

  • Is it slow all the time, or only in one program or website? One program points to that program; everything points to the PC.
  • When did it start? After an update, a new install, or gradually?
  • How old is the PC, and does it have an SSD or a traditional hard drive?

Steps

  1. Restart it. A restart (not just closing the lid) clears many temporary problems. Note how long it has been since the last restart.
  2. Open Task Manager (Ctrl + Shift + Esc) and look at the Processes tab. Click the CPU, Memory and Disk column headers to sort.
    • One program using nearly all CPU, memory or disk: close it. If it is a normal work app, check for updates.
    • Memory constantly above about 85-90%: too many programs open, or not enough RAM for the workload.
    • Disk at 100% for a long time: often a hard drive struggling, a Windows update installing, or a scan running.
  3. Check free disk space (File Explorer > This PC). Under about 10-15% free slows Windows down. See the Disk Space runbook.
  4. Reduce start-up programs: Task Manager > Startup apps. Right-click non-essential apps with "High" impact and choose Disable. Don't disable security software or anything you don't recognise without checking.
  5. Install pending updates: Settings > Windows Update. Restart afterwards. Updates can also be the reason for temporary slowness right after they install.
  6. Scan for malware: Windows Security > Virus & threat protection > Quick scan (see the Malware Cleanup Basics runbook if anything is found).
  7. Check drive health. In PowerShell (run as administrator): 
    Get-PhysicalDisk | Select-Object FriendlyName, MediaType, HealthStatus
    HealthStatus should be Healthy. Anything else: back up data and escalate.
  8. Check browser extensions: if the slowness is in the browser, disable extensions one at a time.
  9. Repair Windows system files (administrator Command Prompt): 
    sfc /scannow
DISM /Online /Cleanup-Image /RestoreHealth
    These can take 10-30 minutes. Restart when finished.
  10. Check heat and power: on a laptop, make sure vents aren't blocked by a soft surface and the power mode isn't set to the lowest setting (Settings > System > Power). Dust in fans causes thermal slowdowns and needs a hardware clean.
  11. Hardware limits: a PC with 4 GB RAM or a very old hard drive will always be slow with modern software. Record this and recommend a RAM or SSD upgrade or a replacement.

Escalate when

  • Drive health isn't Healthy, or the machine makes clicking noises.
  • Slowness returns straight after a restart with no obvious cause.
  • You suspect malware you can't remove.
  • The PC needs a hardware upgrade or replacement (budget decision).
  • It affects many users at once (possibly the network, a server or a bad update).

Ticket note template

Issue: PC is slow (all the time / only in <app or site>)
Started: / Recent changes: 
Task Manager top consumer: <process> at CPU __% | Memory __% | Disk __%
Free disk space: __ GB of __ GB | Uptime before restart: 
Actions: restart [Y/N] | disabled startup items [list] | updates installed [Y/N] | malware scan [clean / found] | sfc/DISM [result]
Drive health (Get-PhysicalDisk): 
Result after actions: Improved / No change
Recommendation / next step:

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How to use this

  1. Search first. Type what the user is describing, like printer offline or locked out. The search reads the whole text of every runbook, not only the titles.
  2. Narrow it down if you want to. The topic links under the search box (Windows, Network, Accounts and so on) trim the list. Click one again, or pick All, to go back.
  3. Open a runbook and read down the page. Symptoms tell you if you are in the right place. Before you start lists the quick questions. Then work through Steps in order, simplest first.
  4. Know when to stop. The shaded Escalate when box lists the signs that it is time to hand the ticket on. If any one of them matches, stop and escalate.
  5. Copy the ticket note. The last section has a note template. Press Copy, paste it into your ticketing system, and fill in the blanks.
Words you will see
Runbook
A written set of steps for one kind of problem, so you do not have to work it out from scratch each time.
First-line support
The first person a user talks to. Fixes the common problems and passes the rest on.
Escalate
Hand a ticket to someone with more access or experience, with notes so they do not have to start over.
Scope
How many people or devices are affected. One laptop and the whole office are very different problems.
Ticket note
A short written record of what was reported, what you tried and what happened.

Why I built this

I'm a computer science student in Toronto and I'm looking for junior IT support and help desk roles. When I started practising troubleshooting, I noticed I knew a lot of individual fixes but not a calm order to try them in, or when to stop and hand a problem on.

So I wrote these twelve runbooks to put that in order for myself, and I built this site so they are easy to search and read. They come from public vendor documentation and common help desk practice. They are not copied from a workplace and they are not real tickets.

They are still a work in progress. If a step looks wrong or something is missing, I would like to know.