Why does my computer keep freezing and lagging?

Computer freezing and lagging is a common issue many users experience. According to a recent study, even with technological improvements, computers malfunction between 11% and 20% of the time (Source). This frustrating problem can lead to lost productivity and data. In this comprehensive guide, we’ll explore the various causes of computer freezes and lags, troubleshooting steps you can take, and preventative measures to help optimize system performance.


There are several common symptoms that indicate a computer is freezing or lagging. The most obvious symptom is when the entire screen freezes and becomes unresponsive to mouse or keyboard input for a period of time. This is often accompanied by the “spinning beach ball” cursor on Mac OS or the “spinning wheel” cursor on Windows. During a freeze, users are unable to click on anything or type anything until the computer unfreezes. Other symptoms include:

– Delayed response time when clicking, typing, or switching between apps and windows. There can be a lag of several seconds before the computer responds.

– Choppy video or audio playback. Videos and music may stutter, pause frequently, or play inconsistently.

– Sluggish performance when opening files, programs, or saving documents. The computer takes much longer than usual to complete basic tasks.

– Input devices like the mouse or keyboard becoming unresponsive even though the screen is not fully frozen.

– Frequent crashing or closing of apps and programs.

– Odd visual artifacts or distortions onscreen.

– Overheating of the computer, resulting in loud fan noises.

These symptoms indicate there is some type of software or hardware issue slowing down the computer and eventually leading to temporary freezes. The underlying causes could range from malware to faulty RAM.


There are several potential causes for a computer freezing or running slowly including too many programs running, hardware issues, malware infections, software conflicts, and more. According to Lenovo, running too many resource intensive programs at once like games, video editing software, or browsers with multiple tabs can overload your RAM and CPU leading to freezes or slow performance.

Hardware issues like CPU/GPU overheating, failing hard drives, or not enough RAM can also cause freezes and slowdowns as your computer struggles to run programs and access data (Minitool). Things like dust buildup causing overheating, fragmented hard drives, and outdated/incompatible components can contribute to these hardware problems.

Malware infections are another common cause according to StellarInfo. Viruses, spyware, and other malware running in the background can consume system resources leading to lag and freezing. They may also corrupt key system files over time.

Finally, software conflicts, bugs, or outdated drivers can also cause system instability and freezing. Things like incompatible programs, Windows updates going wrong, and outdated/buggy drivers can all affect performance and lead to freezes.

Software Issues

One of the most common causes of computer freezing or lagging is having too many programs running in the background [1]. The more apps and browser tabs you have open, the more RAM and CPU resources they consume. If you open more programs than your RAM can handle, it will start using your hard drive space as virtual memory, which is much slower. This can lead to everything slowing down and freezing periodically.

Problems with software can also stem from memory leaks in certain programs [2]. A memory leak is when a program fails to release RAM that it has used, even when it’s no longer needed. Over time, these memory leaks accumulate and eat up your available RAM, resulting in lag and freezing. Rebooting clears the memory and provides temporary relief.

Insufficient RAM is another common software-related cause [3]. If you don’t have enough RAM for the programs you need to run, your system will freeze and lag frequently. Upgrading your RAM can help if you find your memory is consistently at or near full capacity.

Hardware Issues

Hardware problems are a common cause of computer freezing or lagging. For example, an overheating CPU or GPU can lead to throttling and slow performance. Dust buildup in a computer’s fans and heat sinks causes reduced cooling efficiency over time. Replacing old thermal paste between the CPU/GPU and heatsink can greatly improve heat dissipation. Failing hard drives with bad sectors can hang as they struggle to read data. Outdated components like RAM, motherboards, and power supplies degrade over time and may not keeping up with software demands (source). Upgrading to modern hardware can boost speed and responsiveness.

Issues like loose cable connections, faulty RAM, or a failing power supply can cause intermittent freezing or crashes. Checking inside the computer case and reseating components may fix loose connections. Testing hardware with utilities like memtest86 can check for errors. If freezing problems started after upgrading or replacing a component, incompatibility or a defective part may be the issue. Consulting manufacturer system requirements and troubleshooting forums can help identify any component-related problems.

Malware Infection

Malware like viruses, spyware, and cryptojacking malware are a common cause of computer freezing and lagging. When malware infects a computer, it runs in the background utilizing system resources like CPU, RAM, and network bandwidth. This leaves fewer resources for your normal programs and can result in severe performance issues.

Viruses are malicious programs that self-replicate and spread between computers. They often have ‘payloads’ that damage or corrupt files. Spyware secretly gathers data and tracks your activity, transmitting it to third parties. Cryptojacking malware hijacks your computer’s resources to mine cryptocurrency. All these malware types consume resources, creating lag, freezes, and crashes.

Malware usually enters computers through infected websites, email attachments, or downloaded software. Good antivirus software can detect and remove malware, but it’s best to avoid unsafe websites and links altogether. Be very cautious about opening attachments and downloading free software from unknown sources.

If your computer suddenly develops freezing/lagging issues, especially accompanied by unusual disk or network activity, it’s a good sign that malware may have infected your system. Running a full antivirus scan can help identify and eliminate such malicious programs.

Fixes for a Freezing or Lagging Computer

If your computer is freezing or lagging, there are several troubleshooting steps you can try to improve performance:

Close any programs or browser tabs you aren’t using to free up RAM. Having too many programs open at once can overload your computer’s memory and cause freezes or lags. Save your work and close out of any unnecessary apps.

Run a malware scan using antivirus software like Windows Defender or Malwarebytes. Malware infections can slow down your computer and cause performance issues. A scan can detect and remove malware.

Add more RAM if needed. Increasing your RAM allows your computer to multitask and run demanding programs more efficiently. Check your RAM usage to see if an upgrade would help.

Update or replace outdated hardware like your hard drive. A worn out hard drive can cause freezing and crashing. Solid state drives are faster than traditional hard drives.

Update your operating system, drivers, and software. Outdated software can cause conflicts and performance issues. Keep everything up-to-date.

Clean up your hard drive by deleting temporary files and downloads you don’t need. Having lots of clutter slows down your computer over time.


There are several steps you can take to help prevent your computer from freezing up or lagging in the future:

Monitor your computer’s resource usage – Use the Task Manager in Windows (Ctrl + Shift + Esc) to view CPU, memory, and disk usage. If any of those are pegged at 100% consistently, you likely need to close programs, add more RAM, or free up disk space.

Keep your software updated – Install the latest updates for Windows, drivers, and all your programs. Updates often include bug fixes and performance improvements.

Maintain your hardware – Open up your computer yearly to dust it out with compressed air. This prevents overheating. Also replace the thermal paste between the CPU and cooler if it’s older than 3 years.

Only install trusted programs – Stick to downloading software from official sources and creators. Unverified programs have a higher risk of being malware or bloatware which can slow down your system.[1]

Use a popup blocker – Popup ads and notifications put strain on your system resources. Use a browser extension to block unwanted popups.

Check for and remove malware – Run a full system antivirus scan. Malware like viruses, spyware or crypto-miners can heavily tax your CPU and memory.

Upgrade old hardware – If your computer is older than 3-4 years, consider upgrading components like the RAM, graphics card, or swapping the hard disk for an SSD to boost speed.

When to Seek Help

If you have tried the basic troubleshooting steps like updating drivers, scanning for malware, cleaning temporary files, and monitoring resource usage, but your computer continues to freeze or run slowly, it may be time to seek professional help.

Specifically, you should consider taking your computer to a repair shop if:

  • The freezes and slowdowns persist after trying all the above fixes
  • You get frequent blue screen crashes or error messages
  • You notice signs of hardware failure like strange noises from the hard drive
  • You don’t feel technically confident opening up the computer and reseating components
  • You suspect a component like the RAM or hard drive is failing

A computer technician can run diagnostics to pinpoint any failing hardware issues. They also have more advanced tools and knowledge to fully scan for and remove stubborn malware that may be bogging your system down. Seek professional help if you have exhausted your own troubleshooting abilities, as a technician can resolve problems you may not be equipped to handle yourself.


In summary, a computer freezing or lagging can be caused by several issues. The most common causes are insufficient RAM, outdated or incompatible software, hardware failure, malware infections, or too many resource-intensive programs running. To troubleshoot, try updating software and drivers, running virus scans, cleaning the computer interior, closing unnecessary programs, or upgrading RAM. For persistent freezing issues, it may be worth reinstalling the OS or replacing aging hardware components.

Freezing and lagging can be frustrating problems that disrupt productivity. By methodically troubleshooting and addressing the root cause, whether through software improvements, cleaning, upgrades or professional assistance, you can restore smooth performance. Keeping the computer and software optimized, avoiding malware, and not overtaxing the system will help prevent freeze-ups going forward.