Why is my computer so slow all of a sudden? If your Windows 10 suddenly extremely slow, it might be related to malware and viruses, background programs, low disk space, etc. Read this article to figure out more potential reasons and feasible fixes to address this issue.
"My PC was running fine up until last week. All of a sudden I went to turn it on, when it starts up it is too slow and laggy to do anything. I can't even open my settings. Why is my computer so slow all of a sudden? Moreover, how to fix a very slow computer? Thanks!"
If your Windows 10 suddenly extremely slow, it might be caused by malware, background programs, low disk space, outdated software, or insufficient RAM. To diagnose and resolve the problem, perform a malware scan, disable unnecessary startup programs, remove temporary files, and check for available disk space.
1️⃣Malware/Viruses: Run a full scan with Windows Security settings to remove malware and viruses, and check for any suspicious processes in Task Manager.
2️⃣Background Programs: End or disable resource-intensive background programs in Task Manager.
3️⃣Low Disk Space: Delete superfluous files, uninstall unwanted programs using Disk Cleanup or clear junk files using EaseUS Partition Master.
4️⃣Outdated Software/Drivers: Update your operating system or drivers to the latest version.
5️⃣Insufficient RAM: Close unnecessary apps, and consider boosting your RAM.
6️⃣Hard Drive Issues: Check the health of your hard disk and consider defragmenting it, especially for HDDs.
7️⃣Browser Overload: Close any unwanted tabs, and consider using a browser plugin to manage them.
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If you are having the same doubt in your mind, there are some common reasons why Windows 10 is suddenly running so slow.
In short, aside from defective network drivers, faulty or missing drivers for hardware pieces such as the chipset, hard drive, and hard disk controllers might cause your computer to slow down.
Read Also: Brand New ASUS Laptop Running Slow Windows 11
As stated earlier, the first way to delete and remove malware and viruses that slow down the computer is by using Windows Virus & Threat Protection, because this Windows Security feature defends your device against viruses, malware, and ransomware.
It provides real-time security, scans, and customizations to secure your data and system.
Step 1. Please press Win + I to open Windows Settings > select Privacy & Security > click Virus & threat protection.
Step 2. Under the Virus & threat protection tab, click Scan options.
Step 3. In this case, select Full scan > click Scan now. After scanning, restart your PC and reconfirm whether your Windows becomes quicker or not.
Too many running programs in the background could eat up your memory, processing power, laptop battery life, and internet bandwidth. Removing or disabling any TSRs and startup programs that automatically start each time the computer boots can efficiently speed up your PC.
Step 1. Press Win + X > click Task Manager to open it > find what is taking up space on your hard drive and how much memory and CPU they are using.
Step 2. Under the Startup tab, find the app that takes up the most memory in the Process bar > right-click on it > select Disable.
This solution offers two feasible ways to delete temp files or clear junk files. If you want to clean your Windows 10 thoroughly and get better cleaning results, you'd better use the latter way, EaseUS Partition Master.
As a computer runs programs, temporary files are stored on the hard drive. Deleting these temp files can help improve computer performance.
How to Automatically Delete Temp Files in Windows 10/8/7?
This post guides you to delete temp files using Windows Settings. If you're interested, please click this link to get more details.
Step 1. Press Win + E to open File Explorer > right-click on your C drive > click Disk Cleanup.
Step 2. Under the Files to delete tab, select the files you want to delete. In this case, I choose Temporary files and Temporary Windows installation files > click OK.
For some serious hard drive issues that might cause a hard drive overloaded and sluggish, you need the advanced help of professional toolkits! Here, EaseUS CleanGenius is recommended. Use it to clean up all the junk files at once for more free space.
Phase 1. Clean up junk files
Step 1. Download and install EaseUS Partition Master Suite on your PC. Click to download PC Cleaner on panel.
Step 2. Install EaseUS CleanGenius on your PC. To begin with, navigate to "Cleanup" and click "Scan."
Step 3. EaseUS CleanGenius will start immediately to scan all the useless files, select system junk files and invalid entries, and click "Clean" over all your PC.
Step 4. Once completed, you can see clearly how many MBs or GBs of data are cleaned. Click "Done" to finish the process.
Phase 2. Increase the system C drive
If cleaning up junk files doesn't make too much free space for you, another effective solution to Windows 10 suddenly slow problem is to simply extend the C drive with EaseUS Partition Master. Do it with the following steps.
Extend System C drive with unallocated space
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You can update your Windows and the C drive device driver to the latest version if your Windows 10 suddenly extremely slow. Thus, this method includes two phases.
If you are on the Internet when your computer is slow, make sure all browser plugins are up-to-date. Here are the steps. ▶️Press Win + I to open Windows Settings > click Update & Security > check the Windows Update.
Without a doubt, an outdated device driver is responsible for a slow computer. Before updating the driver, you need to figure out the local disk brand, model number that contains your C drive.
Let's show how to update your device driver in Device Manager.
Step 1. Press Win + X > select Device Manager to open it.
Step 2. Under the Disk drives tab, right-click on the Samsung SSD 870 EVO 250GB > select Update driver.
Step 3. In the new pop-up window, choose Search automatically for drivers or Browse my computers for drivers > follow the on-screen instructions.
"Why is my computer so slow all of a sudden?" It might be related to your RAM. So, you can increase your RAM by physically installing extra RAM modules or changing the virtual memory settings in your operating system.
How to Clear Memory and Increase RAM in Windows 10/8/7?
This article offers you four efficient ways to clear memory and increase RAM. If necessary, you can get more details after reading it. Read more >>
As the title suggests, this way also includes two phases: check the hard disk health and/or perform disk defragmentation.
When your Windows 10 suddenly becomes extremely slow, you'd better check whether there are errors or bad sectors on your local hard drive. If there are, you can check and repair hard disk partition errors or file systems via EaseUS Partition Master.
Step 1. Right-click the target partition that may have a problem.
Step 2. Choose "Check" > "Check File System".
Step 3. In the Check File System window, check the "Try to fix errors if found" option by clicking the "Start" button.
Step 4. Please wait patiently. After the process, you can click the "Finish" button to exit the window.
Disk defragmentation is the process of rearranging files on a hard drive to keep related portions together. This can increase computer speed by lowering the time it takes to access files because the hard drive does not have to explore the entire disk for scattered bits of a single file.
Should You Or Should You Not Defrag SSD [Answers & Alternatives]
This post explains whether you should defrag an SSD or not, and the best way to optimize an SSD. Please check it for more details if needed.
Step 1. Type defrag in the search bar > click Run as administrator to open it.
Step 2. Select your targeted drive you want to optimize. Here, I choose the C drive > click Optimize.
▶️By default, Windows will automatically optimize your disks once per week. If you want to set the optimization schedule, please click Change settings > choose Daily, Weekly, or Monthly.
Each tab eats some of your computer's memory and computing resources. When too many tabs are open, these resources might become overloaded, resulting in decreased performance, longer loading times, and possibly even crashes. Thus, you're recommended to end unnecessary tabs.
"Why is my computer so slow all of a sudden?" Thanks to this guide, you don't need to spend hours searching for Windows 10 slow solutions. You have got everything you need to speed up your Windows 11/10/8/7 computers. As you can learn from this full guide, Windows slow issue is caused by many reasons and can be solved by many solutions. You can select a suitable method according to your situation.
Let's take a look at the three hot questions that users are most concerned about Windows 10 slow problem.
1. Can I speed up my computer with Windows 10?
How to speed up Windows 10? Try effective solutions below.
2. How do I stop Windows 10 from lagging?
3. Why is my computer so slow all of a sudden?
A slow computer is often caused by too many programs running simultaneously, taking up processing power, and reducing the PC's performance. Virus infection, malware, hardware issue, high memory usage, etc., all could cause your computer to run slow.
4. How do you find out what is slowing down my PC?
Windows has a built-in tool named Performance Monitor, which can assist you in viewing the computer's activity in real-time. Here is how to do so:
Step 1. Press Win + R to open the Run box > type perfmon > click OK.
Step 2. Once the Performance Monitor opens, go to Data Collector Sets > click System > click System Performance > choose Start.
Step 3. Let this tool test your computer, and it'll last about 60 seconds. Then go to Report > click System, you'll see the Performance report in the System Performance section.
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