I recently received the following question from April Turkett of Morristown, Tennessee.
Two days ago my CPU usage jumped to 100 percent, slowing the computer beyond use. Any ideas on what happened and what to do about it?
An overloaded CPU can make a PC unbearably slow. If the CPU spikes happen rarely and correct themselves quickly, don’t worry about it. But if they keep coming back or don’t go away, you have to find out what’s wrong and fix it.
The most obvious culprit is a virus, spyware, or some other malicious software. Scan your system regularly with a good spy-catching program such as Lavasoft’s Ad-Aware or Patrick M. Kolla’s Spybot Search & Destroy. They’re free, so why not download and use both of them? Next, update your antivirus definitions and run a full virus scan. Set your antivirus program to check for updates and do a full scan automatically at least once a week.
If virus and spyware scans don’t find the problem, it may be due to a malware program that’s too new to be caught. More likely, however, is an unintended problem with an honest program.
If your system’s CPU spike is constant, the software at fault probably loads when Windows boots. Select Start, Run, type msconfig, and press Enter. Click the Startup tab, uncheck suspicious options one at a time, and reboot until the problem stops. Windows 2000 lacks this utility; for this OS, download Startup Control Panel, Mike Lin’s free alternative.
If the processor overload occurs intermittently, note what you’re doing each time the system slows down: the programs you’re running, the Web sites you visited that day, and so on. This information may give you a clue.
In Windows XP and 2000, the Task Manager can show you what’s chewing up CPU cycles. Press Ctrl-Alt-Delete (in Windows 2000, click Task Manager). Choose Processes to see your running programs and subroutines. The CPU column shows the available CPU cycles that each process is running. You can easily find the problem here. The Performance tab shows your CPU usage. Hover the cursor over the Task Manager icon in your system tray to see the current CPU usage in a pop-up window.
Keep the System Idle Process running, even if it’s huge. This process shows the percentage of CPU cycles that are not in use, so in this case, the bigger, the better.
Once you’ve found the processor glutton, get rid of that program. If it’s something you can’t do without, determine whether an updated version with a bug fix is available, or look for a competing program that does a better job.
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