How do I find out why my Windows froze?

If your Windows computer suddenly freezes or becomes unresponsive, there are a few quick troubleshooting steps you can try to diagnose the problem. First, make sure your computer is truly frozen by trying to move the mouse cursor or use the keyboard. If there is no response, your computer is likely frozen.

Force Restart Your Computer

The easiest first step is to force restart your computer. On most PCs, you can hold down the power button for 5-10 seconds to force a shutdown. After waiting a few moments, restart your PC and see if the issue persists. Forcing a restart will clear any temporary software glitches that may be causing the freeze. Just be sure to save your work first!

Check for Overheating Issues

One common cause of computer freezes is overheating. Dust buildup in fans, heatsinks and vents can cause components like the CPU and GPU to overheat. Check for dust buildup inside your desktop computer case. Also ensure your laptop vents have room for airflow and are not blocked when in use.

You can monitor your computer’s temperature using a program like Core Temp or SpeedFan. If you are reaching temperatures above 90°C, overheating could definitely be the issue. Try cleaning your computer or getting a laptop cooling pad to prevent freezing.

Update Your Drivers

Outdated drivers are a prime suspect with computer freezes. Drivers allow your operating system to communicate properly with hardware like your video card, network adapters and storage drives. If these components can’t talk to Windows properly, freezing can occur.

Open Windows Update and install the latest drivers for your hardware. You can also visit your device manufacturer websites, like NVIDIA for graphics drivers or Intel for CPU drivers. Updating drivers to their latest stable versions often resolves freezing issues.

Check for Viruses and Malware

Viruses, spyware, ransomware and other malware are notorious for causing system instability and freezing. Make sure you have antivirus software installed and perform a full system scan. Viruses often manifest as sudden, unexplained computer freezes.

You can use the built-in Windows Security app or download a third party antivirus like Malwarebytes to check for infections. Remove any malware found and restart your computer to see if performance improves.

Analyze Error Logs

Digging into your system error logs can provide clues to what is causing the freezing. Windows keeps detailed logs of hardware, software and system errors that can point you in the right direction.

To view system reliability logs in Windows 10 and 11, go to Start > Control Panel > System and Security > Action Center. Click “View reliability history” and look for crash, error or fault events around the time your computer froze. This can indicate the culprit.

You can also go to Start > Event Viewer, then under Windows Logs look under System, Application and Setup for relevant error events.

Test Your RAM

Faulty RAM, or system memory, is a common hardware source of computer crashes and lockups. You can test your RAM using the Windows Memory Diagnostic tool.

Go to Start and type “Windows Memory” and select “Windows Memory Diagnostic” from the menu. Restart your PC and let the tool run – it will reboot a few times in the process. If errors are found, you likely need to replace your RAM sticks.

Check File System Errors

Corrupted Windows system files can sometimes manifest as freezing. You can scan for errors in Windows’ file system using the Command Prompt.

Open an elevated Command Prompt and run the command “sfc /scannow” – this will scan Windows system files and repair any damage found. Restart when done and test if freezing improves.

You can also run “DISM /Online /Cleanup-Image /RestoreHealth” to repair the Windows image. System file errors can cause all kinds of strange PC issues.

Update Windows

Make sure Windows itself is up-to-date by running Windows Update. Microsoft constantly releases patches and fixes for Windows 10 and 11, so being on an outdated version can lead to instability.

Go to Start > Settings > Update & Security and click Check for Updates. Install all important updates available for your version of Windows. Updating Windows itself often resolves general performance issues.

Check Your Storage Drives

Problems with your storage drives, like hard disk corruption or a failing solid state drive, can result in operating system lockups. Use the built-in Windows tools to scan your drives for errors.

Go to Start > Settings > Update & Security > Backup > More options > Troubleshoot and run the “Check Disk” tool. This will scan your boot drive for file system errors and bad sectors. You can also use “Disk Checking” to scan non-boot drives.

Test Your CPU

Though rare, a faulty CPU can cause random computer freezing in some cases. Test your Windows PC’s processor with Prime95, a free CPU stress testing program.

Download Prime95, disable any overclocking in your BIOS and run the Blend test. If your system crashes or freezes, it may indicate CPU failure. You can also monitor CPU temperatures during the test with a program like Core Temp.

Check Your PSU and Voltages

For desktop PCs, a failing or underpowered power supply unit (PSU) can result in intermittent freezing, especially under heavy system loads. Use software like HWiNFO to monitor voltages from your PSU.

Install HWiNFO and look at the +3.3V, +5V and +12V readings under the sensors tab. If voltages drop below ~10% during system freezes, your PSU may be failing. Replacements are available for most desktop PSU models.

Test Your RAM Slots

If you’ve tested your RAM sticks and they seem fine, a bad motherboard RAM slot could still be the culprit. Try reseating your RAM or rotating sticks between slots one-by-one to test each.

If freezes only happen when a stick is in a certain slot, that motherboard slot is likely faulty. You can shut down the bad slot in BIOS if you have other working slots. Replacing the motherboard may be required in some cases.

Check Temperatures Under Load

While idle temperatures may look fine, overheating under load can still cause freezing. Monitor your CPU and GPU temperatures with a program like Core Temp while gaming or performing other intensive tasks.

If CPU temps exceed 90°C or GPU temps exceed 85°C, overheating could be causing crashes and lockups during load. Improving cooling or reducing system demands may be necessary if high load temperatures are observed.

Reseat Internal Components

Reseating internal components like your graphics card, memory and power cables can fix connectivity issues that may develop over time and lead to freezing.

For desktop PCs, open up the case and remove then reinsert components like your GPU, RAM and SATA/power cables. Faulty connections between components can cause all kinds of problems.

Perform a Clean Boot

Booting Windows into a “Clean Boot” state can help determine if third-party software and services are responsible for freezing issues.

Go to msconfig > Services tab and check “Hide Microsoft Services” then disable all shown services. Go to the Startup tab and disable all startup items. Restart your PC and test if freezing problems continue.

If issues disappear during a Clean Boot, gradually re-enable services and startup items until you isolate the problem program. Update or uninstall the problematic software.

Check Your Motherboard BIOS

An outdated motherboard BIOS can result in compatibility issues and instability. Check your motherboard manufacturer’s website for the latest BIOS updates for your model.

Major BIOS updates can improve memory and CPU compatibility or resolve bugs that may be causing freezing. Just be very careful when flashing BIOS and follow instructions closely.

Test with a Live Linux USB

Booting a live Linux environment from a USB drive can help determine if freezing is related to Windows specifically or your hardware. Download Ubuntu or another Linux distro.

Create a bootable Linux USB and change your BIOS boot order to boot from the stick. If your computer runs fine from the USB, Windows may be the issue. Hardware problems typically persist.


Random computer freezing can stem from a range of software and hardware issues. Start troubleshooting by checking for overheating, monitoring system logs, updating drivers and scanning for malware. Testing components like RAM, the CPU and storage drives can also help isolate faulty hardware.

Freezing issues often arise from inadequate system cooling, file corruption, buggy drivers or viruses. But incorrect BIOS settings, failing hardware or RAM slots can produce similar symptoms. With patience and proper diagnostic steps, you can find and resolve the root cause of most Windows freezing issues.

Troubleshooting Step Details
Force Restart PC Rule out temporary software glitches
Check for Overheating Over 90°C causes freezing
Update Drivers Use Device Manager and vendor sites
Scan for Malware Run antivirus and anti-malware scans
Check Error Logs System, Application, Setup logs
Test RAM Use Windows Memory Diagnostic
Check File System “sfc /scannow” and DISM tools
Update Windows Use Windows Update
Check Drives Run Check Disk and Disk Checking
Test CPU Use Prime95 stress test