When your PC keeps restarting, start by checking the most common causes: overheating, faulty drivers, Windows updates, damaged system files, unstable hardware, and power problems. Disable automatic restart so Windows can display any error, then check recent changes, update Windows and drivers, repair system files, test memory, and inspect the hardware.
Pay attention to when the restart happens and what occurs beforehand. This can help identify whether the problem is related to heat, software, hardware, or power without immediately resetting or replacing the PC.
Why Does My PC Keep Restarting?
A computer can restart because of a software conflict, excessive heat, unstable hardware, an interrupted update, corrupted Windows components, or a power-related problem. Sometimes the restart is intentional because Windows has encountered a serious system error and is configured to reboot automatically.
Microsoft provides official troubleshooting information for unexpected Windows shutdowns and stop errors, so it is worth checking its documentation before making major system changes. Microsoft’s Windows troubleshooting resources can also help identify error codes that appear during a crash.
Common causes include:
- CPU or GPU overheating
- Faulty or outdated device drivers
- Windows Update problems
- Corrupted Windows system files
- Defective or poorly seated RAM
- Power supply problems on desktop computers
- A failing laptop charger or battery
- Recently installed hardware or software
- Automatic restart after a system failure
- BIOS or firmware instability
First: Find Out When the Restart Happens
Before changing settings, pay attention to the pattern. This can narrow the problem considerably.
| What happens | Possible cause |
|---|---|
| Restarts during gaming | Heat, GPU driver, power supply or graphics hardware |
| Restarts shortly after startup | Windows, driver, startup software or hardware problem |
| Restarts during updates | Windows Update or installation issue |
| Restarts when the laptop moves | Power connection, battery or hardware issue |
| Restarts randomly while idle | Driver, Windows, memory, power or scheduled maintenance issue |
This simple observation prevents you from applying complicated fixes unnecessarily.
1. Check Whether Your PC Is Overheating
Heat is one of the first things to investigate when a PC keeps restarting, especially if the problem occurs while gaming, editing video, running demanding software, or performing another heavy task.
Modern processors can reduce performance or shut down when temperatures become unsafe. A desktop with blocked airflow, a laptop with clogged vents, or a cooling system that is no longer working correctly can therefore appear to have a mysterious restart problem.
What to do:
- Turn off the computer and allow it to cool.
- Make sure ventilation openings are not blocked.
- Keep the laptop on a hard, flat surface.
- Check whether fans are running normally.
- Clean accessible dust from the vents carefully.
- Monitor CPU and GPU temperatures while performing the activity that normally causes the restart.
If the machine becomes extremely hot immediately before rebooting, investigate cooling before changing Windows settings. For related symptoms, see our guide on How to Fix Overheating Laptop: 12 Proven Solutions for 2026.
2. Turn Off Automatic Restart to See the Error
Windows may automatically restart after a serious system error. This can make troubleshooting difficult because the computer disappears from the error screen before you have time to read the message.
Temporarily disabling automatic restart can expose the stop code responsible for the failure.
Try this:
- Press Windows + R.
- Type
sysdm.cpland press Enter. - Open the Advanced tab.
- Under Startup and Recovery, select Settings.
- Clear Automatically restart.
- Click OK.
If Windows displays a blue screen afterward, write down the stop code. A message such as a driver-related error can point toward a specific troubleshooting path.
This is also why learning how to fix blue screen error in laptop problems can be useful when repeated restarts are accompanied by a blue screen.
3. Install Pending Windows Updates
A damaged or incomplete update can sometimes cause instability. Microsoft recommends keeping Windows updated because updates include security improvements, bug fixes and compatibility changes.
Open:
Settings > Windows Update
Check for available updates and allow Windows to complete the installation. Keep the computer connected to reliable power during the process, particularly on a laptop.
You can also review Microsoft’s current Windows Update troubleshooting guidance if updates repeatedly fail.
If your system cannot install updates normally, our guide Why Is Windows Update Not Working? 15 Proven Fixes covers additional troubleshooting steps.
4. Update or Reinstall Problematic Drivers
Drivers allow Windows to communicate with hardware such as graphics cards, Wi-Fi adapters, Bluetooth devices and storage controllers. A defective driver can cause crashes or unexpected restarts.
Graphics drivers deserve particular attention if the restart happens during gaming or video-intensive work.
What to do:
- Right-click the Start button.
- Open Device Manager.
- Look for devices showing warning symbols.
- Expand categories such as Display adapters, Network adapters and Bluetooth.
- Open the relevant device and review its driver options.
For graphics hardware, obtain drivers from the manufacturer’s official website rather than relying on random driver-download sites. Microsoft also explains how to update drivers through Device Manager.
5. Check Recently Installed Software
Think back to when the restarting started. Did you install a new application, security program, hardware utility, driver or system-cleaning tool shortly beforehand?
A new application does not necessarily mean it is defective, but timing provides a useful clue.
Try this:
- Uninstall software installed shortly before the problem began.
- Restart the PC.
- Use the computer normally for a while.
- If the problem disappears, reinstall only if you know the software is compatible.
Do not remove essential Windows components simply because their names look unfamiliar. When in doubt, research the exact program before uninstalling it.
6. Test Windows in Safe Mode
Safe Mode starts Windows with a limited set of drivers and services. If the computer becomes stable in Safe Mode, the cause may be related to a third-party driver, startup program or other software rather than basic Windows operation.
Microsoft’s Windows Startup Settings documentation explains how Safe Mode and related startup options work.
You can reach advanced startup options through:
Settings > System > Recovery > Advanced startup > Restart now
From the recovery environment, choose the startup option for Safe Mode.
7. Repair Corrupted Windows System Files
Windows includes built-in tools for checking and repairing system components. If important files have become corrupted, system instability can follow.
Open Terminal or Command Prompt as an administrator and run:
sfc /scannowAllow the scan to finish. Do not close the window simply because the percentage appears to pause.
If SFC reports that it cannot repair everything, Microsoft recommends using the Deployment Image Servicing and Management tool in appropriate circumstances. A commonly used command is:
DISM /Online /Cleanup-Image /RestoreHealthAfter DISM completes, run SFC again:
sfc /scannowThese commands are preferable to downloading unofficial “Windows repair” utilities from unknown websites.
8. Test Your RAM
Unstable memory can cause crashes, freezes and unexpected restarts. This becomes more important if you recently upgraded RAM or the computer has multiple memory modules.
Windows includes Windows Memory Diagnostic.
Press Windows + R, enter:
mdsched.exeThen choose the option to restart and check for memory problems.
If you recently installed RAM, make sure the module is compatible with your motherboard or laptop and properly seated. For users considering a memory upgrade, our guide on How to Upgrade Laptop RAM explains the compatibility factors to check first.
9. Check Your Power Supply or Charger
A desktop computer needs a stable power supply, while a laptop depends on a charger, battery and internal power-management hardware.
If your PC restarts whenever the processor or graphics card suddenly demands more power, the power system deserves attention.
For a desktop:
- Check that the power cable is firmly connected.
- Avoid damaged or loose cables.
- Consider whether the power supply is old or undersized.
- Check whether the problem began after installing a more powerful GPU or other hardware.
For a laptop:
- Inspect the charger and connector for visible damage.
- Test whether the issue occurs only on battery or only while charging.
- Use the manufacturer’s recommended charger.
Do not open a power supply yourself. Internal components can retain dangerous electrical energy even after the computer is unplugged.
10. Check for High RAM Usage and Resource Pressure
High memory usage does not automatically mean your RAM is defective. Windows uses available memory for applications, caching and background tasks. However, a program with a memory leak or too many active applications can make the system unstable.
Press Ctrl + Shift + Esc to open Task Manager and select Memory.
Look for applications consuming unusually large amounts of RAM.
If memory is consistently near its limit, close unnecessary programs and investigate the application using the most memory. You can also read Why Is My Computer Using So Much RAM? 12 Proven Fixes for 2026 for a deeper explanation.
11. Check Event Viewer for Restart Clues
Windows Event Viewer records many system events, including unexpected shutdowns and hardware-related warnings.
Press Windows + X and open Event Viewer. Then look under:
Windows Logs > System
Look around the exact time the restart occurred. You may find critical or error events that provide additional context.
One commonly encountered event is Kernel-Power. It can indicate that Windows detected an unexpected loss of power or shutdown, but it does not necessarily identify the underlying cause by itself.
For that reason, do not assume that a Kernel-Power event automatically means the power supply is defective. Treat it as a clue and compare it with temperature, driver, hardware and system information.
12. Disconnect Recently Added Hardware
If the restarts began after connecting a new USB device, installing a graphics card, adding storage or upgrading memory, temporarily reverse the change.
This is a simple troubleshooting technique because it changes only one variable.
For example, imagine a desktop computer that worked normally for months but started restarting after a new graphics card was installed. Removing the card and testing the previous configuration can help determine whether the new hardware, its driver, its power requirements or another installation issue is involved.
13. Check BIOS and Firmware Carefully
BIOS or UEFI firmware controls important aspects of hardware initialization. A firmware problem or unstable configuration can cause serious system instability.
If you recently changed BIOS settings, restore the relevant settings to their default values and test the computer again.
Do not update BIOS firmware simply because the computer is restarting. Firmware updates can be useful when the manufacturer specifically recommends one for your hardware or for a problem you are experiencing.
Use only the manufacturer’s official support page for BIOS downloads and instructions.
14. Turn Off Overly Aggressive Overclocking
If you have manually increased CPU, GPU or RAM performance settings, return them to their standard configuration temporarily.
Overclocking can be stable under some workloads and unstable under others. A computer that appears normal during ordinary browsing may restart when a demanding application places a sustained load on the hardware.
Testing at default settings is therefore a useful diagnostic step.
15. Use System Restore or Recovery Options
If the computer was stable recently and the problem appeared after a driver, application or configuration change, System Restore may help when restore points are available.
System Restore can roll certain system settings and software configurations back to an earlier state without functioning as a complete personal-file deletion process.
Before using any major recovery option, back up important files. Microsoft provides information about System Restore and Windows recovery options.
A Practical Example: A PC That Restarted During Gaming
Consider a desktop computer that was restarting every 20 to 30 minutes during demanding games but worked normally when browsing the web.
The owner could have immediately reinstalled Windows, but the pattern suggested a load-related problem. Temperature monitoring showed that the graphics card was becoming unusually hot. After cleaning the case, improving airflow and checking the cooling setup, the restarts stopped.
The important lesson is not that overheating is always the answer. It is that the circumstances surrounding the restart provide valuable evidence.
Another computer might restart only after Windows begins installing an update. In that case, Windows Update troubleshooting would make more sense than changing the cooling system.
What to Do If Your PC Still Keeps Restarting
If the first 15 solutions have not solved the problem, stop making random changes. At this stage, use a more controlled diagnostic process.
- Write down the exact time of each restart.
- Record whether the computer was idle or under heavy load.
- Check Event Viewer around that time.
- Record any blue-screen stop code.
- Test Windows in Safe Mode.
- Run Windows Memory Diagnostic.
- Check CPU and GPU temperatures.
- Disconnect recently installed hardware.
- Restore default BIOS performance settings.
- Back up important files before advanced recovery.
If the computer still restarts after a clean Windows environment and hardware checks, professional hardware diagnosis may be more appropriate than repeatedly reinstalling Windows.
Frequently Asked Questions
Why does my PC keep restarting randomly?
Random restarts can be caused by overheating, defective drivers, Windows errors, memory instability, power problems, BIOS settings or failing hardware. Check when the restart occurs and use Event Viewer and Windows diagnostic tools to narrow down the cause.
Can overheating make a PC restart?
Yes. Excessive CPU or GPU temperatures can cause a computer to reduce performance, shut down or restart to protect hardware. This is especially worth checking if the restart happens during gaming or other demanding workloads.
Can bad RAM cause a computer to keep restarting?
Yes. Unstable or defective memory can cause crashes, freezes and unexpected restarts. Windows Memory Diagnostic is a useful first test, although persistent memory errors may require additional hardware testing.
Should I reinstall Windows if my PC keeps restarting?
Not as the first step. Reinstalling Windows can remove software-related problems, but it will not repair overheating, defective RAM, a failing power supply or other physical hardware problems. Diagnose the cause first and back up important files before using major recovery options.
Why does my PC restart when gaming?
Gaming places substantial demand on the processor, graphics hardware and power system. If restarting happens only during demanding games, check temperatures, graphics drivers, power delivery, GPU stability and overclocking settings.
How do I stop Windows from restarting automatically after an error?
Open System Properties, go to Advanced > Startup and Recovery > Settings, and temporarily clear Automatically restart. This can give you enough time to record a blue-screen stop code if one appears.
Can Windows Update cause repeated restarts?
Windows normally restarts during certain update operations, but repeated unexpected restarts can indicate an update or system problem. Check Windows Update history and use Microsoft’s Windows Update troubleshooting guidance when installations repeatedly fail.
Is Kernel-Power always caused by a bad power supply?
No. Kernel-Power events can appear after an unexpected shutdown, but they do not automatically prove that the power supply is defective. Investigate other possible causes such as overheating, hardware instability, drivers and power interruptions.
Final Thoughts: Get the Restarting Problem Under Control
When your PC keeps restarting, the most effective approach is not to jump immediately to a factory reset or replace expensive hardware. Start with the circumstances surrounding the restart, then check temperature, automatic restart settings, Windows Update, drivers, system files, memory, power and recently installed hardware. Use Windows’ built-in diagnostic tools to collect evidence instead of guessing.
In many cases, the solution is relatively simple once the pattern becomes clear. A laptop that restarts under heavy workloads may need better cooling, while a desktop that became unstable after a hardware upgrade may need its new component or driver checked. If the problem continues after software troubleshooting and hardware testing, backing up your files and getting the machine professionally diagnosed is the safer next step.
The goal is not merely to stop one restart. It is to identify why the PC keeps restarting so the problem does not return a few days later.