How to fix a slow computer: Keep your PC running smoothly

How to fix a slow computer
(Image credit: Getty Images)

Remember when you bought your computer? It was fast, apps loaded quickly, and the world was your oyster. Sadly, though, devices slow down with age; drives get slower, components fail, and the accumulation of files and software can mean you need to learn how to fix a slow computer.

Thankfully, there are a few things you can try, and many of them won’t cost you money. While there are some rules of thumb which we’ll mention below, you may be able to keep the best home computers going for a little while longer.

How to fix a slow computer

Regularly sweeping your PC for unused files and leftover pieces of apps you’ve deleted is recommended, even if it’s just every few months.

Secondly, if your device is upgradeable and is still running off an HDD (hard disk drive), we’d recommend looking into SSDs (solid-state drives). These have no moving parts so tend to last longer, and they’re faster, too.

There are a few things you can try to help speed up the performance of a Windows PC.

Check which apps open at startup

Many apps can give you the option to open them automatically when you turn on your PC or log into it, but if too many try and open at once your machine’s performance will take a hit.

If you press Ctrl-Shift-Escape together, you’ll instantly open your Task Manager. From here, tap the Startup tab to see what’ll open at login. Now, you can disable each one individually.

Clear resource-hungry applications

Sticking with the task manager, the “Processes” tab will give you a look at which applications are using up your memory (don’t be surprised to see Google Chrome there, particularly if you have plenty of tabs open).

This way, you can close down applications by clicking on the process and then clicking “End Task”.

We’d avoid closing “Background processes” unless you’re sure you know what you’re doing, though – these can sometimes be confusingly named and you may end up closing something you need, or worse still end up losing work you haven’t saved.

How to fix a slow computer

(Image credit: Getty)

Close apps that are running in the background

It can be easy to miss apps that are open, but are found within the taskbar. These can range from Google Drive sync, to game launchers, to messaging apps, but you may not want them all open at once.

Thankfully, you can click the small chevron on the right-hand side of your taskbar to see open apps, then right-click each to find the option to remove them.

Clear away files and apps that you don't need

Almost everything you delete on your PC will be sent to your Recycle Bin, which can itself then become a sizable resource hog. Right-click and select “Empty Recycle Bin” to clear it.

You should also check documents and files you don’t need and be ready to delete them. It’s easy to become a digital hoarder, but if you’re using an old HDD things can really slow down.

You can also delete applications to make more room. Press the Windows logo on your taskbar (or press your Windows key) and search for “Add or Remove Programs” to instantly open a list of your installed applications.

You may be surprised by what you find, but you can safely uninstall applications from this window.

Check your power settings

Windows will change how much power your device uses if you need to manage, say, a laptop battery, but it’ll also manage power consumption on a desktop, too.

Open the Start menu (Windows key again), and search for “Power & Sleep settings”. Here you’ll find a slider that’ll let you move between energy-saving and best performance.

You can also set a “Power Plan” through the “additional power settings” option, letting you customize your power to energy consumption ratio with more granularity.

Cleanup and defrag

Windows offers a couple of handy tools for computer maintenance. The first is Disk Cleanup, which you can find by searching for it in the Start menu.

Here, you can select a drive and then the type of files you want to get rid of. Once you’ve ticked them, simply hit “Clean up system files”. If you’ve got multiple drives, you’ll need to repeat this step for each.

Defragmenting is something you’ll only need to do if you have a HDD, and while Windows will generally do this on a weekly cadence, it’s worth knowing how to do manually. Think of it as a “file wrangler” that grabs disparate pieces of your drive and realigns the files for smoother operation.

You’ll need to go to “This PC” through the Start menu, right-click your drive, and then click Properties, then Tools. There, you should find an option for Optimize and defragment drive. Click Optimize, then highlight the drive in question and click Analyze.

If Analyze is grayed out, you can’t defrag because you’re using an SSD instead.

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Lloyd Coombes
Customer Advisor, Computing

Lloyd Coombes is Top Ten Reviews' Computing Customer Advisor, and a freelance writer with a specialism in tech, gaming, and fitness. Since starting out as a blogger, he’s written for sites like IGN, TechRadar, and more.

An expert on all things Apple ever since he got a second-hand iMac, Lloyd can regularly be found testing software on iPhone, iPad, Apple Watch and Mac — when he’s not testing the platforms themselves, that is. He’s also’s Games Editor, and a podcaster.

When he’s not writing, you can probably find him running after his son, playing Destiny 2, or at the gym.