Heavy CPU usage prevents your computer from operating at its highest efficiency while you are using it. CPU usage might spike for several reasons. A program running in the background might be using it, such as an anti-virus application or other system-scanning utilities. An improperly closed system-intense program can also eat up your CPU's resources. Whatever the case, you can at least partially clear your CPU's usage using already-installed Windows utilities.
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Step
Press down the "Ctrl" and "Alt" keys on either the left or right side of the keyboard. Press the "Del" key. This opens a new full-screen options menu in Windows 7. Click "Start Task Manager." This closes the options menu and opens the "Windows Task Manager" window on top of all other open windows.
Step
Check current CPU usage by looking at the bottom of the window. The "Task Manager" displays the value as a percentage beside "CPU Usage."
Step
Click the "Processes" tab at the top of the window. This menu displays all processes currently operating on your PC. It tells you the name of the process, the name of the user for whom the process is running, its current CPU usage, its current memory usage and, if available, a description.
Step
Click on "CPU" so that the "Task Manager" sorts all processes by their current CPU usage. Click so that the arrow points down, ordering the processes by most CPU usage to least.
Step
Click processes at the top of the list. These are the processes using your CPU's resources. Click "End Process." A dialog box opens asking if you want to end the process. Click "End Process." Repeat this until your CPU usage is cleared.