Fix: High CPU Usage (At 100%) Without Any Running Programs
Written by: Stelian Pilici
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Experiencing a sudden surge in CPU usage to 100% when you’re not actively running any applications or tasks can be both perplexing and exasperating. High CPU usage without any apparent reason can lead to a range of issues, including sluggish performance, unresponsiveness, and even system crashes. It’s crucial to diagnose and address the underlying causes to restore your computer to its optimal working condition. In this comprehensive guide, we will delve into the various potential factors contributing to this seemingly unexplained high CPU usage and offer you a detailed roadmap to identify, troubleshoot, and resolve the issue effectively. By following the step-by-step recommendations provided in this article, you will be able to reclaim your system’s performance and prevent future occurrences of this frustrating problem.
Here is a list of all the possible causes of high CPU usage (At 100%) without any running programs:
Malware: Malware (eg. Trojan Miners, Trojan Downloaders, Adware) can cause high disk usage by creating unnecessary processes that run in the background.
System errors: System errors can also cause high disk usage. These errors can be caused by corrupt system files, software conflicts, or other issues.
Disk errors: Disk errors can cause high disk usage by preventing the system from accessing data stored on the hard drive.
Startup programs: Too many startup programs can cause CPU at 100% for no reason. These programs are launched automatically when the system boots up, which can put a strain on the system’s resources.
Power Settings: Your computer’s power settings can also impact CPU usage. If you’re using a Windows PC, consider changing your power plan to “High Performance” or adjusting individual settings within the plan to prioritize system performance. Go to Settings > System > Power & Sleep > Additional power settings, and select “High Performance” or customize your current plan.
Outdated hardware or drivers: Using outdated hardware or drivers can cause CPU at 100% for no reason. Updating to the latest version can help improve system performance and resolve high disk usage issues
Troubleshoot Potential Hardware Issues: In some cases, high CPU usage may result from hardware-related issues. Overheating can cause your CPU to throttle its performance to prevent damage. Ensure proper ventilation and cooling for your system by cleaning dust from fans and vents, and consider using a cooling pad if you’re using a laptop.
Check Background Processes: Even when no applications are running, your computer may still have background processes consuming CPU resources. To check the background processes, open the Task Manager (Ctrl + Shift + Esc) and navigate to the Processes or Details tab. Look for processes that are using a significant amount of CPU resources and research the process name to determine if it’s a necessary system process or a potential issue. You can also right-click on the process and select “End Process” to stop it, but be cautious as ending essential system processes can cause system instability.
If you are experiencing high disk usage on your computer, we recommend following the steps outlined in the guide below to troubleshoot and resolve the issue.
How To High CPU Usage (At 100%) Without Any Running Programs
This guide may appear overwhelming due to the number of steps and numerous programs that are being used. We have only written it this way to provide clear, detailed, and easy-to-understand instructions that anyone can use to fix their computer. Please perform all the steps in the correct order. If you have any questions or doubts at any point, stop and ask for our assistance.
To fix High CPU Usage (At 100%) Without Any Running Programs, follow these steps:
STEP 1: Check your computer for malware and viruses
In this first step, we will check your computer for malicious programs that might cause high disk usage. To do this we will manually search and uninstall malicious programs, remove malicious browser extensions, and finally run an anti-malware scan.
1. Uninstall malicious programs
First, we will manually check if any unknown or malicious programs are installed on the computer. Sometimes adware and browser hijackers can have a usable Uninstall entry that can be used to remove them.
Windows 11Windows 10Windows 8Windows 7
Press the Windows key + I on your keyboard to open the Settings app.
First, open Windows Settings by pressing Windows+I on your keyboard. You can also right-click your Start button and select “Settings” from the list.
In the Settings app, click on “Apps” and then “Apps & features”.
When Settings opens, click “Apps” in the sidebar, then select “Apps & Features”.
Find the malicious program in the list of installed apps and uninstall it.
In Apps & Features settings, scroll down to the app list and search for unknown or suspicious programs. To make things easier, you can sort all installed programs by their installation date. To do this, click “Sort by” and select “Install date”.
Look out for any suspicious program that could be behind all the drama – anything you don’t remember downloading or that doesn’t sound like a genuine program. When you find a malicious program, click the three dots button beside it and select “Uninstall” in the menu that appears.
If you have checked your computer for malicious programs and did not find any, you can proceed with the next step in this guide.
Follow the prompts to uninstall the program.
In the next message box, confirm the uninstall process by clicking on Uninstall, then follow the prompts to uninstall the malicious program.
Make sure to read all of the prompts carefully, because some malicious programs try to sneak things in hoping that you won’t read them closely.
Press the Windows key + I on your keyboard to open the Settings app.
Press the Windows key + I on your keyboard to open the Settings app. You can also ope the Settings app by clicking the Start button on the taskbar, then select “Settings” (gear icon).
In the Settings app, click on “Apps”.
When the “Windows Settings” window opens, click on “Apps“. By default, it should open “Apps and Features” but if it doesn’t, select it from the list on the left.
Find the malicious program in the list of installed apps and uninstall it.
In Apps & Features settings, scroll down to the app list and search for unknown or suspicious programs. To make things easier, you can sort all installed programs by their installation date. To do this, click “Sort by” and select “Install date”.
Look out for any suspicious program that could be behind all the drama – anything you don’t remember downloading or that doesn’t sound like a genuine program. When you find a malicious program, click on it and select “Uninstall” in the menu that appears.
If you have checked your computer for malicious programs and did not find any, you can proceed with the next step in this guide.
Follow the prompts to uninstall the program.
In the next message box, confirm the uninstall process by clicking on Uninstall, then follow the prompts to uninstall the malicious program.
Make sure to read all of the prompts carefully, because some malicious programs try to sneak things in hoping that you won’t read closely.
Go to “Program and Features”.
Right-click on the Start button in the taskbar, then select “Programs and Features”. This will take you directly to your list of installed programs.
Search for malicious program and uninstall it.
The “Programs and Features” screen will be displayed with a list of all the programs installed on your computer. Scroll through the list until you find any unknown or suspicious program, then click to highlight it, then click the “Uninstall” button.
Look out for any suspicious program that could be behind all the drama – anything you don’t remember downloading or that doesn’t sound like a genuine program.
If you have checked your computer for malicious programs and did not find any, you can proceed with the next step in this guide.
Follow the on-screen prompts to uninstall malicious program.
In the next message box, confirm the uninstall process by clicking on Yes, then follow the prompts to uninstall malicious program. Make sure to read all of the prompts carefully, because some malicious programs try to sneak things in hoping that you won’t read closely.
Open the “Control Panel”.
Click on the “Start” button, then click on “Control Panel“.
Click on “Uninstall a Program”.
When the “Control Panel” appears, click on “Uninstall a Program” from the Programs category.
Search for malicious programs and uninstall them.
The “Programs and Features” screen will be displayed with a list of all the programs installed on your computer. Scroll through the list until you find any suspicious or unknown program, then click to highlight it, then click the “Uninstall” button.
Look out for any suspicious program that could be behind all the drama – anything you don’t remember downloading or that doesn’t sound like a genuine program.
If you have checked your computer for malicious programs and did not find any, you can proceed with the next step in this guide.
Follow the on-screen prompts to uninstall malicious program.
In the next message box, confirm the uninstall process by clicking on Yes, then follow the prompts to uninstall malicious program. Make sure to read all of the prompts carefully, because some malicious programs try to sneak things in hoping that you won’t read closely.
If you are experiencing difficulty while attempting to uninstall a program, you can use Revo Uninstaller to completely remove the unwanted program from your computer.
Now that the malicious programs have been removed from your computer, we can proceed with the next step in this guide.
2. Clean up your browser
Next, we will remove spam notifications, malicious extensions, and change to default any settings that might have been changed by malware. Please note that this method will remove all extensions, toolbars, and other customizations but will leave your bookmarks and favorites intact. For each browser that you have installed on your computer, please click on the browsers tab below and follow the displayed steps to reset that browser.
ChromeFirefoxMicrosoft EdgeInternet Explorer
Reset Chrome for Windows to default settings
We will now reset your Chrome browser settings to their original defaults. This will reset your startup page, new tab page, search engine, and pinned tabs. It will also disable all extensions and clear temporary data like cookies. Your favorites, history, and saved passwords will not be cleared.
Click the three dots in the top-right corner and then click on “Settings”.
Open Chrome and click on the menu button (represented by three vertical dots) in the top right corner of the window. In the dropdown menu that opens, click “Settings“.
Click “Advanced”.
Chrome’s “Settings” should now be displayed in a new tab or window, depending on your configuration. In the left sidebar, click on the “Advanced” link.
Click “Reset and clean up”.
In the left sidebar, under the “Advanced” section, click on “Reset and clean up“.
Click “Reset settings to their original defaults”.
In the main window, the “Reset and clean up” section is visible, as shown in the screenshot below. Click on “Reset settings to their original defaults“.
Click “Reset settings”.
A confirmation dialog will now be displayed, detailing the components that will be restored to their default state should you continue with the reset process. To complete the restoration process, click on the “Reset settings” button.
(Optional) Reset Chrome Data Sync.
In case a malicious extension reinstalls itself even after performing a browser reset, you have an additional option to reset the data sync for your browser. To do this, navigate to chrome.google.com/sync and click on the Clear Data button.
Reset Firefox for Windows to default settings
We will now reset your Firefox browser settings to their default. The reset feature fixes many issues by restoring Firefox to its factory default state while saving your essential information like bookmarks, passwords, web form auto-fill information, browsing history, and open tabs.
Click the three horizontal lines in the top-right corner and then click on “Help”.
Click on Firefox’s main menu button, represented by three horizontal lines. When the drop-down menu appears, select the option labeled “Help“.
Click “More troubleshooting information”.
From the Help menu, click on “More troubleshooting information“.
Click on “Refresh Firefox”
When the “Troubleshooting Information” page opens, click on the “Refresh Firefox” button.
Confirm that you want to reset your browser settings.
To finish the reset process, click on the “Refresh Firefox” button in the new confirmation window that opens.
Click “Finish”.
Firefox will now close itself and will revert to its default settings. When it’s done, a window will list the information that was imported. Click on “Finish“.
Your old Firefox profile will be placed on your desktop in a folder named “Old Firefox Data“. If the reset didn’t fix your problem you can restore some of the information not saved by copying files to the new profile that was created. If you don’t need this folder any longer, you should delete it as it contains sensitive information.
Reset Microsoft Edge to default settings
We will now reset your Microsoft Edge browser settings to their default. This will reset your startup page, new tab page, search engine, and pinned tabs. It will also disable all extensions and clear temporary data like cookies. Your favorites, history, and saved passwords will not be cleared.
Click the three dots in the top-right corner and then click on “Settings”.
In the top right corner, click on Microsoft Edge’s main menu button, represented by three horizontal dots. When the drop-down menu appears, click on “Settings“.
Click on “Reset Settings”.
On the left side of the window, click on “Reset Settings“.
Click on “Restore settings to their default values”.
In the main window, click on “Restore settings to their default values“.
Click “Reset”.
A confirmation dialog should now be displayed, detailing the components that will be restored to their default state should you continue with the reset process. To complete the restoration process, click on the “Reset” button. Microsoft Edge will now erase all your personal data, browsing history, and disable all installed extensions. Your bookmarks, though, will remain intact and still be accessible.
Reset Internet Explorer to default settings
We will now reset your Internet Explorer browser settings to their default. You can reset Internet Explorer settings to return them to the state they were in when Internet Explorer was first installed on your computer.
Go to “Internet Options”.
Open Internet Explorer, click on the gear icon in the upper-right part of your browser, then select “Internet Options“.
Select the “Advanced” tab, then click “Reset”
In the “Internet Options” dialog box, select the “Advanced” tab, then click on the “Reset” button.
Click on “Reset”.
In the “Reset Internet Explorer settings” section, select the “Delete personal settings” checkbox, then click on the “Reset” button.
Click on “Close”.
When Internet Explorer has completed its task, click on the “Close” button in the confirmation dialogue box. Close your browser and then you can open Internet Explorer again.
3. Run a scan with Malwarebytes Anti-Malware Free
Now, we will install Malwarebytes to scan and remove any infections, adware, or potentially unwanted programs that may be present on your computer.
Malwarebytes stands out as one of the leading and widely-used anti-malware solutions for Windows, and for good reason. It effectively eradicates various types of malware that other programs often overlook, all at no cost to you. When it comes to disinfecting an infected device, Malwarebytes has consistently been a free and indispensable tool in the battle against malware. We highly recommend it for maintaining a clean and secure system.
Download Malwarebytes for Windows
You can download Malwarebytes by clicking the link below.
After the download is complete, locate the MBSetup file, typically found in your Downloads folder. Double-click on the MBSetup file to begin the installation of Malwarebytes on your computer. If a User Account Control pop-up appears, click “Yes” to continue the Malwarebytes installation.
Follow the On-Screen Prompts to Install Malwarebytes
When the Malwarebytes installation begins, the setup wizard will guide you through the process.
You’ll first be prompted to choose the type of computer you’re installing the program on—select either “Personal Computer” or “Work Computer” as appropriate, then click on Next.
Malwarebytes will now begin the installation process on your device.
When the Malwarebytes installation is complete, the program will automatically open to the “Welcome to Malwarebytes” screen.
On the final screen, simply click on the Open Malwarebytes option to start the program.
Enable “Rootkit scanning”.
Malwarebytes Anti-Malware will now start, and you will see the main screen as shown below. To maximize Malwarebytes’ ability to detect malware and unwanted programs, we need to enable rootkit scanning. Click on the “Settings” gear icon located on the left of the screen to access the general settings section.
In the settings menu, enable the “Scan for rootkits” option by clicking the toggle switch until it turns blue.
Now that you have enabled rootkit scanning, click on the “Dashboard” button in the left pane to get back to the main screen.
Perform a Scan with Malwarebytes.
To start a scan, click the Scan button. Malwarebytes will automatically update its antivirus database and begin scanning your computer for malicious programs.
Wait for the Malwarebytes scan to complete.
Malwarebytes will now scan your computer for browser hijackers and other malicious programs. This process can take a few minutes, so we suggest you do something else and periodically check the status of the scan to see when it is finished.
Quarantine detected malware
Once the Malwarebytes scan is complete, it will display a list of detected malware, adware, and potentially unwanted programs. To effectively remove these threats, click the “Quarantine” button.
Malwarebytes will now delete all of the files and registry keys and add them to the program’s quarantine.
Restart your computer.
When removing files, Malwarebytes may require a reboot to fully eliminate some threats. If you see a message indicating that a reboot is needed, please allow it. Once your computer has restarted and you are logged back in, you can continue with the remaining steps.
4. Double-check for malicious programs with HitmanPro
Finally, we will scan the computer with HitmanPro to ensure that no other malicious programs are installed on your device.
HitmanPro is a second-opinion scanner that takes a unique cloud-based approach to malware scanning. HitmanPro scans the behavior of active files and also files in locations where malware normally resides for suspicious activity. If it finds a suspicious file that’s not already known, HitmanPro sends it to its clouds to be scanned by two of the best antivirus engines today, which are Bitdefender and Kaspersky.
Although HitmanPro is shareware and costs $24.95 for 1 year on 1 PC, there is no limit on scanning. The limitation only kicks in when there is a need to remove or quarantine detected malware by HitmanPro on your system and by then, you can activate the one-time 30-days trial to enable the cleanup.
Download HitmanPro.
You can download HitmanPro by clicking the link below.
HITMANPRO DOWNLOAD LINK (The above link will open a new web page from where you can download HitmanPro)
Install HitmanPro.
When HitmanPro has finished downloading, double-click on “hitmanpro.exe” (for 32-bit versions of Windows) or “hitmanpro_x64.exe” (for 64-bit versions of Windows) to install this program on your computer. In most cases, downloaded files are saved to the Downloads folder.
You may be presented with a User Account Control pop-up asking if you want to allow HitmanPro to make changes to your device. If this happens, you should click “Yes” to continue with the installation.
Follow the on-screen prompts.
When HitmanPro starts you will be presented with the start screen as shown below. Click on the “Next” button to perform a system scan.
Wait for the HitmanPro scan to complete.
HitmanPro will now begin to scan your computer for malicious programs.
Click on “Next”.
When HitmanPro has finished the scan, it will display a list of all the malware that it has found. Click on the “Next” button to have HitmanPro remove the detected items.
Click on “Activate free license”.
HitmanPro may now require to activate the free 30-days trial to remove the malicious files. To do this, click on the “Activate free license” button to begin the free 30 days trial and remove all the malicious files from your computer.
When the malware removal process is complete, it will display a screen that shows the status of the various programs that were removed. At this screen, you should click on the Next button and then if prompted you should click on the Reboot button. If HitmanPro does not prompt you to reboot, please just click on the Close button.
STEP 2: Run the System File Checker (SFC) tool
One potential cause of high disk usage is the presence of system errors. To check for and repair these errors, you can use a tool called the System File Checker (SFC).
The SFC tool scans all protected system files on your computer and replaces any files that are corrupt or damaged with a cached copy that is stored in a compressed folder at %WinDir%\System32\dllcache. By running the SFC tool, you can help ensure that your system is functioning properly and fix any issues.
Open Command Prompt as Administrator.
To open the Command Prompt as an administrator in Windows, type “cmd” in the search bar and then right-click on the Command Prompt result and select “Run as administrator” as shown in the image below. A User Account Control (UAC) prompt will appear asking for permission to allow the program to run. Click “Yes”.
Type “sfc /scannow”.
You will now be presented with a black screen called the ‘Administrator: Command Prompt’. On this screen, type “sfc /scannow” to scan for and repair any corrupt system files.
Restart your computer.
Restart your computer if sfc /scannow repaired files. System File Checker may or may not prompt you to restart but even if it doesn’t, you should restart anyway.
Run again sfc /scannow.
Run again sfc /scannow to check if the files were repaired.
STEP 3: Run the Disk Check tool
Another tool that can help identify and fix issues that may be causing high disk usage is the Disk Check tool, also known as “chkdsk.”
This tool checks your hard disk for errors and can fix any issues it finds. To use the Disk Check tool, you will need to open the command prompt and enter the “chkdsk” command followed by the drive letter (e.g., “chkdsk C:”). You can also add the “/f” flag to the command to instruct the tool to fix any errors it finds. By running the Disk Check tool, you can help ensure that your hard disk is functioning properly and fix any issues that may be causing high disk usage.”
Open Command Prompt as Administrator.
To open the Command Prompt as an administrator in Windows, type “cmd” in the search bar and then right-click on the Command Prompt result and select “Run as administrator” as shown in the image below.
A User Account Control (UAC) prompt will appear asking for permission to allow the program to run. Click “Yes”.
Type “chkdsk /f /r”
You will now be presented with a black screen called the ‘Administrator: Command Prompt’. On this screen, type “chkdsk /f /r” to repair any errors on your hard drive.
Restart your computer
The Disk Check tool may require you to restart your computer in order to complete the scan and repair process. Type “Y” and click on Enter, then restart the computer.
A CHKDSK command can take a long time, especially when performed on larger drives. Once it’s done, however, it will present a summary of results including total disk space, byte allocation, and, most importantly, any errors that were found and corrected.
STEP 4: Disable any unnecessary startup programs
Startup programs are applications that automatically launch when you start your computer. While some of these programs may be necessary for your system to function properly, others may be unnecessary and can consume system resources, including disk usage. Disabling unnecessary startup programs can help improve system performance and reduce high disk usage.
Open the Task Manager by pressing the Ctrl + Shift + Esc keys on your keyboard simultaneously.
In the Task Manager, go to the “Startup” tab and disable any programs that you do not need to start automatically when you turn on your computer.
Keep in mind that some startup programs may be essential to the functioning of your system, so be careful not to disable any important programs.
STEP 5: Use Device Manager to find hardware issues
In some cases, high disk usage may be caused by hardware errors or issues with hardware devices connected to your computer. To check for and troubleshoot these types of errors, you can use the Device Manager built-in into Windows.
Open Device Manager.
To access the Device Manager, type “devmgmt.msc” into the search bar on the Start menu and select “Device Manager” from the list of results.
Find hardware devices that work properly.
In the Device Manager, you can view a list of all the hardware devices connected to your computer and check for any errors or issues. If you see a yellow exclamation point next to a device, it may indicate a problem with that device. You can right-click on the device and select “Update driver” or “Troubleshoot” to try and fix any issues.
We hope this guide helps you fix the CPU at 100% for no reason. If you have any other questions or need further assistance, don’t hesitate to start a thread in our forum.
Meet Stelian Pilici
Stelian leverages over a decade of cybersecurity expertise to lead malware analysis and removal, uncover scams, and educate people. His experience provides insightful analysis and valuable perspective.
