Why Your PC is Slowing Down and How to Fix It

At some point, just about everyone who uses a computer has experienced that frustrating moment when things start to slow down. Your system lags, programs take ages to load and simple tasks like opening a browser or file seem to take an eternity.

Here’s the thing: slowdowns don’t just happen out of nowhere. You might have too many startup apps, background processes hogging resources or a hard drive low on space. It could be as simple as your computer needing a good restart or an overdue update running in the background.

Thankfully, it is not all doom and gloom. Most of the time, these issues are easy to diagnose and even easier to fix. With a few tweaks and some smart maintenance, you can get your PC running almost as fast as it did the day you first set it up.

And if you do end up needing to purchase an entirely new computer, these are the best desktop PCs for 2024 and the best laptops for 2024.

Task Manager is like a magic crystal ball

Think of Task Manager as a window into your PC's health. The app gives you insight into what's taxing the processor, how much memory something is taking up and even how much network data a program has used. 

An easy way to open Task Manager in Windows is by pressing the Ctrl + Shift + Esc keys together. Alternatively, you can also click on the magnifying glass on the Taskbar and search for Task Manager.

Task Manager’s default view only shows basic information, like which apps are running -- useful if you already know which one you want to close. To view what really matters, click Details in the left pane.

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By default, this list is broken down into Apps and Background Processes. It's refreshed constantly, with the various columns continually updating. My advice is to let Task Manager run for a few minutes and watch it. Watch for apps that shoot up to the top of the list, then disappear a few seconds later. Look for processes that stay at the top of the list with high memory or CPU use. Not sure what one of the processes is? Google its name to find out more. 

To close an app or process that you suspect may be partly responsible for slow performance, click on the listing, then click End Task. 

Also read: Want to download Windows 11? You need to do these two things first

Four more common reasons for a slow PC

There are far too many apps and services to create a succinct list of what's likely slowing down a PC, but that doesn't mean there aren't likely culprits. Here are some of the top issues that we all experience on a PC. 

Antivirus scans

After watching your system running slow with Task Manager open, you may have noticed that your antivirus software is routinely near the top of the list. Antivirus software can slow down your system while it's actively scanning your computer for malware and viruses. 

Instead of letting your antivirus program scan whenever it sees fit, schedule it to run at times when you're not likely to be using your PC, such as overnight or during your lunch hour. Changing the schedule for scans will depend on the program you use, but generally, you can open the app and go to the settings pane to customize the schedule. 

If you use Windows Defender as well, you can disable the periodic scanning option by opening the Windows Security app and navigating to Virus & threat protection > Microsoft Defender Antivirus options. Turn the toggle for Periodic scanning off and see if that makes any difference.

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Too many apps are running at login 

If your PC takes forever to be responsive after you log into your Windows account, then you probably have too many apps trying to run at startup. You can edit the list of apps and services that begin running when you log in to your computer by opening Task Manager and clicking on the Startup apps option (tiny meter icon in the left pane). 

Go through the list and remove anything that you don't need to have loaded and ready the moment your PC turns on by clicking the app name, followed by Disable.

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Some web browsers are resource hogs

Your web browser could be the culprit, especially if you've lost count of the number of windows and tabs you have open. Each browser window and tab takes up memory and processing power and, over time, that will begin to slow down your PC. 

You can view a breakdown of extensions and tabs that could be to blame in Task Manager by clicking on the arrow next to your browser's name. Alternatively, if you use Chrome, it has a built-in task manager of its own. Launch it by pressing Shift+Esc while using Chrome, or click on the menu button > More Tools > Task manager. 

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If you find that your browser is often causing your PC to slow to a crawl, try a different browser or keep an eye on how many tabs or windows you have open at a given time. 

Your operating system or its drivers might be outdated

Drivers act as middlemen between your hardware and software. When they are outdated, the components can struggle to communicate with each other, resulting in slow performance, crashes, or worse, random errors. Similarly, an outdated operating system lacks new features and performance improvements, which can be a problem when newer software demands more from your old system.

To install the latest driver and OS updates, head over to the Windows Settings app and click Windows Update. Use the Check for updates button to scan for any new updates and take the time to install those that are available one by one.

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Battle-tested solutions

There's a wide range of methods available for troubleshooting and speeding up your PC. Below are some steps to take that should, at the very least, temporarily speed up your slow computer:

Close running apps when you're done. Make sure they're not running in the notification tray (next to the volume and Wi-Fi indicators). When you close some apps, such as Slack, they keep running in the background. Usually, you can completely close apps that keep running by right-clicking on the app icon and selecting quit or exit. If you no longer use an app, consider getting rid of it for good by uninstalling it through the Control Panel. Pause OneDrive syncing. This is something even Microsoft admits can slow down your computer. Pause OneDrive by clicking on the OneDrive icon in the notification tray, select More and then Pause syncing. Check available storage space and hard drive health. If your hard drive or SSD is running out of space or is getting old, it could be failing. I use CrystalDisk Info (Standard Edition) to get basic insights into my drives. It's a free app that quickly scans your drives and tells you their current health status. If you aren't comfortable testing your hard drive, take your computer to a technician who can properly diagnose the issue and, if required, upgrade your storage. Regularly turn off your computer. Don't just restart it; completely power it off and walk away for a few minutes. This gives your computer a chance to clear out memory and start fresh the next time it's turned on. 

If none of the above suggestions speeds up your computer to a level that you're happy with, you can try reducing animations, changing themes and toggling other Windows-specific settings. If you're trying to get remote help, make sure you know the best way to take screenshots on Windows 11. If you're more of an Apple household, you're in luck: We have recommendations for speeding up a slow Mac, too.