Having high CPU usage can cause your computer to run slowly and freeze up. There are several potential causes of high CPU usage and solutions you can try to fix the problem.
Determine The Cause of High CPU Usage
The first step is to identify what is causing the CPU usage spike on your computer. Here are some common culprits:
Malware or Viruses
Malware infection is one of the most common reasons for unexpectedly high CPU usage. Viruses, spyware, and ransomware can infect your system and use up CPU resources to do malicious tasks.
To check for malware, run a full system scan with your antivirus software. Antivirus programs like Avast, Norton, and Malwarebytes can detect and remove malicious programs hogging your CPU. You can also use the built-in Windows Defender tool.
Faulty Apps
Buggy, unoptimized, or memory-leaking applications can sometimes cause CPU usage spikes. Apps that continue running in the background even when not in use are particularly problematic.
Check the process list in the Task Manager to identify any application using high CPU. Then research online whether the app has a history of high CPU usage issues. Updating to the latest version may resolve any bugs. As a workaround, you can terminate background processes when not needed.
Overuse of Browser Tabs
Having too many active browser tabs open can overweight your CPU. Google Chrome in particular is known to consume significant CPU resources with many tabs.
Try closing down tabs you aren’t actively using. Switch to a lighter web browser like Firefox or Microsoft Edge if the problem persists. Use extensions like The Great Suspender to automatically suspend unused tabs and free up system resources.
Hardware Failure
In rare cases, a faulty CPU fan, failing hardware, or overheating can cause abnormally high CPU usage.
Use hardware diagnostics tools like CPU-Z and Core Temp to monitor your CPU temperature, frequency, load, and identify any potential hardware defects. You may need to replace thermal paste or clean your computer if overheating is the source of high CPU.
Troubleshoot Processes With Task Manager
The Windows Task Manager provides detailed insight into which processes and applications are using up your CPU power.
To open task manager, press Ctrl + Shift + Esc or right-click the taskbar and select “Task Manager”. Go to the “Processes” tab.
Here you can review the CPU, memory, and disk usage of different applications and services. Sort by CPU to identify the most resource intensive processes.
Google Chrome, Windows Explorer, System Idle Process, and Antimalware Service Executable tend to use high CPU, but that alone is not necessarily indicative of a problem.
Look for any unusual processes using very high CPU like svchost.exe or Service Host: Local System. Research these online to determine if they are indicative of malware.
You can right-click a process and select “End task” to forcefully terminate it, freeing up CPU usage. But be careful, as this can cause instability if done on essential system processes.
Adjust Power Settings
Your Windows power plan settings can impact CPU usage and cause your computer to feel sluggish.
Go to Control Panel > Power Options and ensure the plan is set to Balanced or High Performance instead of Power Saver.
Power Saver can cause CPU throttling and make background tasks utilize more CPU trying to finish quicker before the next throttling event. Setting a high-performance plan keeps CPU speed more consistent.
Disabling BIOS power management like Enhanced Halt State (C1E) and Intel Turbo Boost can also help reduce unexpected CPU usage spikes in some instances. But make sure to re-enable these for power efficiency when your issue is resolved.
Check Startup Items
Too many programs starting up when Windows boots can lead to high background CPU usage. Open Task Manager, then go to the Start up tab.
Here you can see all programs configured to auto-start with Windows. Disable any unnecessary applications, background services, and bloatware to optimize startup CPU impact.
Tools like CCleaner and Autoruns also help manage startup programs. Avoid technical utilities that promise to “boost speed”, as most are ineffective or malware.
Update Device Drivers
Outdated, buggy, or incorrect device drivers can sometimes cause CPU usage problems after Windows updates.
Use Device Manager to check for any drivers showing errors or alert signs. Expand each device category and right-click to update drivers.
For specific hardware like GPU, motherboard, or Wi-Fi adapters visit the manufacturer website to download the latest official drivers. This keeps them optimized and stable.
Clean Up Disk
A cluttered hard drive with low free space can result in high CPU usage as Windows struggles to find free space.
Use the Disk Cleanup utility to remove unnecessary Windows files and temporary data. Uninstall any unused applications. Delete downloads, documents, and media you no longer need.
Defragmenting your hard drive helps reorder files and speed up system performance. Use the built-in Disk Defragmenter tool or Defraggler for this.
Upgrading to a faster hard drive like an SSD provides a major performance and CPU usage boost for older systems. But even a clean mechanical drive helps.
Check For Overheating Issues
Excessive heat can cause CPU hardware to slow down or work harder to compensate, resulting in high usage.
Monitor your CPU and system temperatures under load using a program like Speccy or Core Temp. Idle CPU temps above 40°C/105°F or load temps over 90°C/195°F generally indicate overheating issues.
If overheating, ensure your case cooling and CPU fan/heatsink are operating properly. Remove dust buildup on heat sinks and intake vents. Consider upgrading to higher CFM case fans or a CPU liquid cooler. Replacing thermal paste between the CPU and heatsink can also lower temperatures.
Also ensure proper airflow space around your PC. Don’t let the hot air exhaust blow right into a wall or enclose in tight spaces. Air conditioning also helps lower ambient temperatures.
Identify Bottlenecks
A weaker or faulty hardware component bottlenecking your CPU can cause high usage.
Use monitoring to check if CPU usage correlates with high RAM usage, indicating insufficient memory. Upgrading RAM often improves performance.
High disk usage alongside high CPU can indicate a slow hard drive bottleneck. Switch to an SSD or use a larger mechanical drive.
Insufficient CPU cores/threads can also cause heavy load and spikes. Increasing core count with a CPU upgrade helps. Identifying hardware bottlenecks helps avoid wasting money on unnecessary upgrades or replacements during troubleshooting.
Reset Windows
If you’ve exhausted all other options, doing a full reset or clean reinstall of Windows may be necessary to fix high CPU usage problems.
Back up your personal data first. Under Settings, go to Update & Security > Recovery and select Get started under the Reset this PC section.
This will reinstall Windows fresh and wipe all your programs and customizations, so only use as a last resort. Reinstalling from a Windows bootable USB drive can also resolve software-related high CPU usage problems.
Conclusion
Persistent high CPU usage can stem from malware, buggy software, hardware defects, heat issues, and system misconfigurations. Carefully monitor your CPU usage and processes to identify the culprit. Cleaning up unnecessary programs and services provides the easiest fix. Hardware upgrades like added RAM, a new CPU, or SSD may be warranted if high usage stems from aging components. But reinstalling and resetting Windows is an option if all else fails. Staying on top of updates and eliminating bottlenecks keeps your system running smooth.
