Computer slow all of a sudden (Reasons + Solution)
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The frustration of Computer slow all of a sudden is always irritating. Programs operating in the background are one of the most frequent causes of a slow computer. TSRs and starting programs that launch automatically each time the computer boots should be removed or disabled. To check which applications utilize how much CPU and RAM in the background: Activate “Task Manager.”

When the computer is turned on, you wait as the operating system loads. You used the computer without any issues yesterday, so why is it so slow now? Although not unusual, this experience suggests that something is wrong and typically happens for a purpose.
Reasons and solutions for computer slow all of a sudden:
1. Antivirus Scanning:
Antivirus software is essential for preventing digital diseases from infecting your PC, but it may also be a resource hog when scanning your computer. Most AV packages offer real-time monitoring, but all reliable security programs check your hard drive and memory for suspicious files and activity. But scanning can make your PC sluggish.

Open Task Manager and check your disk use whenever you see a slowdown. Select the “Disk” column under the “Processes” tab to view the programs using the disk. Your AV is probably searching for malware if it takes up space on the disk. Maintaining routine scans is important, so don’t stop them. Set the scan schedule to a time when you aren’t often using the computer instead.
2. Outdated or Corrupt Drivers:
Your computer may run poorly for reasons other than bad network drivers, including broken or missing drivers for any hardware components. The chipset, hard drive, and hard drive controllers, as well as the graphics card drivers, are the most likely offenders. First, look in Device Manager if you think there might be a driver problem.
While holding down the Windows key, press the “R” key to bring up the Run dialog box. Then enter devmgmt.MSC after typing it. Look for devices in Device Manager that have an exclamation point next to them. The icon indicates an unreliable or missing driver.
Even without exclamation points, you might still have a driver issue because Windows might have installed a minimal driver version but not the correct one. The manufacturer of your PC is the best source for drivers. In the support section of the company’s website, look for downloads for your model number.
If you built your PC, try identifying the specific component that requires a new driver and go to the manufacturer’s website. Start with the chipset (motherboard) and move on to the other devices if you are unsure which one is malfunctioning.
3. Network Issues:
Does your computer only lag when you try to use the Internet to do something? Your network connection may be the issue. Almost everything we do on a computer nowadays depends on a connection to the Internet, so a slow Ethernet or Wi-Fi connection can give the impression that your entire PC is slow.
To test, try launching offline software on your computers, such as a music player that plays mp3 files from your hard drive, photo viewing and editing software, or just a word processor for writing documents.
Does your computer still run slowly? If not, your network connection might be having issues. If so, it’s critical to identify whether the issue is internal to your computer or external. To see if the network connection improves, try switching networks or moving the computer to a different location.
To test your Internet connection before and after that change, go to speedtest.net. Any download speed that is slower than 25 Mbps will probably feel slow.
If your network is the source of the issue, seek assistance from your Internet service provider or an administrator. The most likely cause of a computer issue that appears to be internal is a driver that is out of date, missing, or corrupt. The most recent network drivers can be found and downloaded on the manufacturer’s website. (If your connection is particularly bad, you might have to do this from another computer.)
It’s also worth remembering that your Internet browser could be the issue, even if your network and hardware are just fine. Try a different browser to test it out. Download Chrome if Edge is your go-to browser. Try Firefox if you often use Chrome. A faulty extension or plug-in may create a bottleneck if your browser is the issue.
4. Other Hardware Issues:
A sluggish computer might be caused by hardware faults other than hard disk issues. This is particularly valid if your motherboard, CPU, GPU, or RAM malfunctions. One or more RAM sticks could be broken, interfering with the computer’s attempts to address specific sections. In addition to sluggish performance, you can encounter shutdowns, blue screens, or unexpected reboots.

You may occasionally notice some indication of the issue, but not always. Memtest86 is a reliable diagnostic for examining memory. But don’t let the name fool you. The software can run on ARM chips in addition to the x86 architecture. Extract the zip files after downloading the software. An executable file that you can use to make a bootable USB drive can be found within. Your computer must be started from this drive for the utility to have complete access to the memory.
Since motherboard faults might present themselves in ways similar to OS problems, they are more difficult to diagnose. Reinstall your OS and check to see if the issue reappears. If possible, you might try taking your discrete GPU out of the computer to see if the issue resolves itself.
5. Overheating:
Computers produce a significant amount of heat. The typical operating temperature of a CPU is between 100°F and 150°F (38°C and 66°C), and additional components like graphics processor units (GPUs) exacerbate the issue. So, your computer may become slower if your PC isn’t draining heat effectively, actively or passively.
Some complex chipsets can command components to slow down to prevent component damage when overheating. You’ll undoubtedly notice slow performance on your PC if this is the case. We can look at processor temperatures to obtain a good picture of the overall temperature within the computer because the CPU is typically the hottest component.
The free HWMonitor tool by CPUID is an excellent method to monitor CPU temperatures. The CPU of your machine may be found by using the program you downloaded and installed. A section with temperatures will appear when you click the plus symbol to expand the information. Temperatures above 150°F could indicate problems, and the CPU shouldn’t ever reach 200°F.
High temperatures that appear out of nowhere could signal that your fan has failed, that your vents are blocked or clogged, or that there isn’t enough thermal paste between your CPU and its heatsink. To fix the problem, use a can of compressed air to remove the lint and dust. Check your fans if your CPU temperature is still excessive. You can track fan speeds using the free Speed Fan tool, and if your PC supports diagnostics, you should run them to ensure the fans are functioning properly.
6. Too Many Background Services Running:
When you get into your computer, do you see a lot of programs opening up simultaneously? If so, you might be running too many services and background processes. These programs typically don’t affect your OS much, but their effects can mount when you add additional programs over time.
Because the impacts of this phenomenon build up, a single program probably is to blame if your computer suddenly becomes slow. A particularly resource-hungry program or one badly written could be the blame. Considering this might be the reason for your sudden slowdown, consider any recent application installations.
Start by uninstalling the most recent one first. Check your computer’s performance after each installation to see if it has improved. If you require these apps, the best course of action is to stop them from starting up automatically. This will guarantee that the software only runs when you need it, saving resources while it isn’t in use.
We’ll go to Task Manager as we did earlier, but this time click on the “Startup” tab to verify startup programs. To arrange the applications by whether or not they start up automatically when you log in, click on the “Status” column heading. Look over any “Enabled” and turn off any that you don’t want to run continuously.
7. Your Hard Drive Is Failing:
A broken hard drive is one of the most basic ways for a computer to run slowly. Even solid state drives eventually fail, especially if your primary hard Disk is mechanical. Because issues can be intermittent or sporadic, diagnosing a faulty hard drive can be challenging, especially if only a few sectors are affected. Still, the remainder of the drive is functioning normally.

I’ve seen some systems startup startups function as they should, only to crash when the OS tries to access a specific service or DLL in a bad sector. The software Check Disk, which has the fitting name, is one technique to check for faults. Reopen the command prompt and enter the following instruction:
/r chkdsk c
If Windows is installed on a different drive, swap out the letter “c” with the partition’s letter. Command Prompt will ask you if you want to run Check Disk at the next boot because the operating system is now using the Disk. Then restart your computer after typing “y” and pressing Enter.
Be patient, as this process could take some time, depending on the size of your hard drive. The /r switch instructs Check Disk to make an effort to “repair” errors, but this typically entails locating bad sectors, turning them off, so they are never used again, and (if feasible) transferring the existing data to good sectors of the drive.
Utilizing diagnostic tools is another technique to examine the drive for faults. You can access built-in dialogs from several PC manufacturers by clicking a hotkey on the keyboard before booting up. Meanwhile, you can use third-party applications that operate both inside and outside the operating system. Back up your data and replace the Disk as soon as possible if diagnostics reveal a drive issue.
8. Low Disk Space:
How much disk space are you left with? If you’re hard drive is full or almost full, your computer may perform slowly and exhibit other odd behaviors like stalling or crashing. For a few different reasons, an overloaded hard disk might be problematic for the operating system. The OS first uses a swap or page file, a portion of hard drive space, as virtual RAM.
The OS will temporarily unload RAM contents to the Hard Disk, where they can be retrieved and reloaded into memory as needed, freeing up memory for more immediate usage. Although your computer can set aside hard drive space for this, the swap file expands or contracts based on the required space.
Your computer won’t be able to make the best use of RAM if there isn’t enough room to expand the swap file’s size. A full hard drive is also a less effective one. Because there isn’t enough free space to reorganize the current files, it takes longer to index and reference files and can cause the hard Disk to be more fragmented.
This is smaller of an issue now that solid-state drives are so common, but even a single millisecond can add up. If your computer has limited storage, try unloading or eliminating useless files. If you don’t frequently clean them out, the recycle bin and your downloads folder can serve as repositories for various data.
Try Windows 11’s built-in Storage Sense tool if you’ve removed all the obvious files but are still nearing your storage limit. You may clean out temporary files and other directories using this utility. Another tool we enjoy is Piriform’s CCleaner.
9. Your Computer Might Have A Virus:
Although there are many distinct kinds of viruses, many of them can make your computer run slowly. Some types of malware (unwanted harmful software) try to avoid detection and consume the least amount of system resources. Others will prevent you from using your computer until the virus has been eliminated. But even the most minimal infections leave some sort of mark on system performance.
Some of the unmistakable indicators of malware are frequent, mysterious pop-up windows, browser redirects while browsing the web, and changes to your system settings that you did not initiate. If you notice that your computer is suddenly performing slowly and you think a virus might be to blame, open the performance monitor to see what is using up so many system resources.
Launch the Task Manager by pressing the keyboard shortcuts to shift + ctrl + ESC, and then select the “Performance” tab to get there. Regarding your PC’s speed, slow hard drives or insufficient memory are typically (but not always) the main bottlenecks. Check them first. You can quickly identify the problematic hardware with Performance Monitor, but Resource Monitor allows for even more in-depth reporting.
To start the program, select the “Performance” tab, scroll to the bottom and click “Open Resource Monitor.” You can find more specific details on which processes are using up all your RAM, CPU, and disk usage in Resource Monitor. You may have identified the offender if a certain process utilizes many resources.
If unsure, you can verify the authenticity of the software by running a rapid search on Google for the name of the process. Use a reliable antivirus program to scan your computer for viruses if you think you might have one. After the scan, we advise using Malwarebytes because it works well to discover and remove malware alongside AV software.
Be ready for the potential that some of the more dangerous viruses demand a full format and reinstallation of the Operating System.
Conclusion:
It’s easy to get irritated when your Computer slows all of a sudden. These problems tend to arise at the worst moments, but by methodically examining the symptoms, you’ll be able to spot the issue and fix it like a pro.
FAQs:
Why is my Windows 10 so slow all of a sudden?
Programs operating in the background are one of the most frequent causes of a slow computer. TSRs and starting programs that launch automatically each time the computer boots should be removed or disabled. To check which applications utilize how much CPU and RAM in the background: Activate “Task Manager.”
How do I find out what is slowing down my computer?
Performance Monitor is a built-in diagnostics tool for Windows. It may examine the activity on your computer in real-time and through your log file. Its reporting function can help you determine what’s slowing down your PC—Open Run and type perfmon to get Resource and Performance Monitor.

Stephany Cole, Author and editor at the same time at InstantLobby — Her main focus is to develop strategic editorial and research initiatives for InstantLobby. Her work includes writing, assigning and editing “pillar” collections and other editorial content on technologies and trends of vital importance to CS and IT and business leaders. Topics include Modern technologies such as AI and robotic process automation and IT trends, digital transformation. She spearheaded InstantLobbys Thought series; started from scratch, topics include edge computing, gaming, hyper-automation and high-performance computing, including complex business issues affecting IT and business leaders such as data trust. Previously, she served as executive knowledge and fun.