8 easy ways to speed up a slow PC

No matter how fast and snappy your computer felt when you first bought it, there will almost certainly come a time when it starts to feel slow and unresponsive. But our experts can help.

Perhaps your device takes forever to start up, or maybe there’s a frustrating lag every time you launch an app or click a button. Some computers show their age in different ways – by running out of storage space, for example, or the battery life is shorter than it used to be.

Here, we run through some straightforward maintenance tasks. By tweaking a few simple settings, you can potentially speed up your computer, reclaim lost storage and boost battery life.

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1. Disable startup apps

Apps that run automatically whenever your computer boots up can slow down your PC and sap valuable system resources.

You can disable most startup apps and re-enable any you realise you need. However, you should always leave security apps enabled.

• On Windows 11

Right-click the taskbar and select Task Manager. If you don’t see Startup apps on the left, click the More details button (three lines) to reveal it, then Startup apps. Right-click apps you don’t need and choose Disable.

• On Windows 10

Right-click the taskbar and select Task Manager. If you don’t see a Startup tab at the top, click More details > Startup. Right-click any startup apps you don’t need and choose Disable.

• On a Mac

Go to Apple logo > System Settings > General > Login items. Click any unnecessary apps listed under Open at Login, then choose the minus (-) button below.

2. Turn off unnecessary features

Windows and macOS use fancy visual effects to make them feel nicer to use, but these use up computing power. Turning some of these non-essential effects off can free up resources and improve your PC's performance.

• On Windows

Click Start, type Performance then click Adjust the appearance and performance of Windows. In the Performance Options window, select Adjust for best performance. Choose Apply and restart your PC.

• On a Mac

Click Apple logo > System Settings > Desktop & Dock. Work through the options here, disabling any that relate to visual effects, such as switching Magnification to off, selecting Scale Effect for the Minimise windows using setting, disabling Animate opening applications and so on.

Discover the best laptops for all budgets, based on our expert independent tests.

3. Scan for malware and system problems

Malware can cause computers to feel slow, so it's worth running a virus scan to rule out the possibility of an infection.

Precise instructions will vary depending on the security software you use. So if you're not sure, check for instructions on the manufacturer's website.

You can also use Windows’ built-in troubleshooters to scan your system for other problems that might be affecting general performance. Click Start, type troubleshoot then press Enter and click Other troubleshooters (Windows 11) or Additional troubleshooters (Windows 10).

To find out which programs cope effortlessly with viruses and phishing attacks, see our guide to the best antivirus.

4. Change your battery settings

As your laptop ages, its battery becomes less efficient – this is frustrating because it requires more frequent recharging and depletes more quickly. 

Closing down apps, lowering screen brightness, and switching to Airplane Mode (when you don't need wi-fi or Bluetooth) all reduce the rate at which power drains. Keeping your laptop clean and making sure it has plenty of airflow around its case can also help to extend battery life – dust and blocked vents can cause your laptop's fans to work harder, which drains the battery faster.

Tweaking some settings on your device can help, too.

• On Windows

Go to Start > Settings > System > Power & battery (Windows 11) or Start > Settings > System > Battery (Windows 10). Here you can enable Battery Saver, which helps your battery last longer by limiting background activities. There’s also an option to enable Battery Saver automatically when your charge drops below a specified percentage (@). Try setting this to 20% or higher.

It's also worth checking the Screen and sleep options to make sure you're not wasting precious battery power by leaving your screen on for too long when you're not using it.

• On a Mac

Go to Apple logo > System Settings > Battery and set Low Power Mode to Only on Battery. Click the i button next to Battery Health and make sure that Optimised Battery Charging is enabled – this will help reduce battery ageing. 

Click the Options button at the bottom of the Battery settings screen and enable Slightly dim the display on battery, set Wake for network access to Only on Power Adapter and switch on the Optimise video streaming while on battery option if it’s available.

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5. Look after your battery

Caring for your laptop's battery can help to lengthen its overall lifespan. For instance, it's good practice to try and keep your battery level somewhere between 20% and 80% wherever possible. Microsoft also recommends making sure your computer's battery regularly drains below 50%, as this can help to lower the rate at which the battery cells deteriorate.

If you're not going to use your laptop for a while, it's a good idea to leave a little charge left in the battery before you store it away – somewhere just below 50% is ideal. Apple recommends having your battery charged to around 50% if you're going to store your Mac long term.

And it's best to avoid using or charging your PC if it’s very hot.

Find out what to do if your laptop is plugged in but not charging.

6. Considering switching to an SSD

A few years ago, we might have suggested upgrading your computer's Ram to prolong its lifespan. But adding memory to modern computers is unlikely to offer more than a minor performance bump, and some laptops don't allow Ram upgrades at all.

There's another hardware upgrade that might be worth considering, however. If your computer's internal system drive is an old mechanical hard disk (HDD), then switching to a fast solid-state drive (SSD) will provide your device with a massive speed boost. 

• On Windows

You can see what type of system drive you have by opening the Task Manager and clicking Performance. Look under Disk 0 (C:) and it will say SSD or HDD.

• On a Mac

Go to Applications > Utilities > Disk Utility. Click on Macintosh HD, then click the Info button. If it says Yes under Solid State, that means you already have an SSD.

Unfortunately, upgrading your computer's internal system drive yourself can be tricky and might not be possible if your laptop case can't be opened.

We recommend using Which? Trusted Traders to locate a reputable computer repair centre near you and check if they offer an SSD upgrade service. Make sure to back up all your data before carrying out the upgrade.

7. Update your operating system

Modern computer operating systems such as Windows and macOS are designed to check for updates automatically. But you can also update your device manually, if you're experiencing performance problems.

• On Windows 10 

Click Start > Settings > Update & Security > Windows Update. Choose Check for updates.

Note that official support for Windows 10 ends on 14 October 2025, meaning Microsoft will no longer offer fixes, new features or security updates after that date. Find out more about what action you need to take when Windows 10 ends security support.

• On Windows 11

Click Start > Settings > Windows Update. Choose Check for updates.

• On a Mac

Click Apple logo > System Settings > General > Software Update to scan for available updates.

Considering a new Mac? Find out which model is suits your needs and budget, plus which retailers have the best prices – see best Macbooks.

8. Update your apps and programs

Updating apps that came with your computer or that you installed from its built-in app store is straightforward. Doing so ensures you have the latest features, security patches, and performance improvements.

• On Windows

Load up the Microsoft Store (you can search for it within the Start menu), then select the Library icon > Get updates.

• On a Mac

Open the App Store and click Updates > Update all.

Updating apps you've installed from elsewhere will vary. Security tools will update themselves automatically and most other modern apps carry out an update check whenever you run them.

Some software may require you to check for updates manually, however. You'll usually find an option for this in the File, Help or Settings menu.

Updating drivers on Windows

On Windows devices, drivers are bits of software designed to help your computer's hardware work smoothly. Updating or reinstalling drivers can sometimes fix hardware-related performance problems. But indiscriminately updating your PC's drivers can sometimes introduce further problems, so we’d recommend letting your computer manage drivers automatically.

Windows Update will install any essential driver updates for you and running Windows' troubleshooters will reinstall drivers that could be causing problems. If in doubt, Tech Support members can always contact our friendly team for further help.

When it's time to buy a new PC

If you've worked through the steps above and your device is still causing you problems, it might be time to start shopping around for a new model.

Before you buy, make sure you check our round-up of the best laptops. 

Rremember that opting for a refurbished model could save you money. Make sure you buy from a trusted vendor and check your purchase is supported by some kind of guarantee. Our guide on how to buy a second-hand laptop has more details.

Here are some other scenarios where replacing your old PC is the best way forward:

• If your operating system (OS) is no longer supported and you can’t upgrade – lots of Windows 10 users will face this soon as Microsoft is ending support for this OS on 14 October 2025, and many older computers don’t meet Windows 11’s strict minimum system requirements.
• If your PC is 5+ years old and needs a repair – it’s usually cheaper to repair a broken computer than it is to buy a new one. But the older your computer is, the less cost effective it becomes to repair it. If it’s more than five years old, you could be better off replacing it with a newer model.
• Your battery no longer holds its charge – if you mainly use your computer at a desk, this might be less of an issue. But if you need to use your laptop on the go and its battery is non-replaceable, then you may need to buy a new model. Our laptop reviews will help.

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Additional reporting by Tom Morgan.

Updated: this article was originally published on 9 October 2024. It was checked and republished February 2025.