Why is my CPU at 100% usage during simple tasks

I don’t know if that is expected from a computer or not. I don’t see why it would be. During simple tasks like opening a new window my CPU will go to 100% usage and stay there, making the task (like opening something new or closing something) really slow. I have a 1.2Ghz Athlon so I don’t think that would make it unable to perform everyday tasks. Do I have a bottleneck somewhere or is it just the fact that my processor isn’t fast enough? Right now that i’m not opening or closing anything CPU usage is only 10%, but if I open google it shoots to 100%. However it handles that pretty well and only stays at 100% for a second or so sometimes it takes 20 seconds to open or close a window and stays at 100% usage the whole time.

DISCLAIMER: I’m PussyCow’s husband; just noticed your question, happen to be a graduate student in computer science, and thought I’d respond.

Yes, this is (sort of) expected behavior, but (generally) only for a (very) short time. Much depends on what programs/processes/applications are running at the time; if, for instance, you’re converting a .WAV to an .MP3, you can expect 100% CPU usage for quite a bit. Simply opening and closing a window should not (ordinarily) exhibit this behavior. There is more than likely something else running/happening (e.g., image display, anti-virus program, memory management, etc.) of which you’re not aware happening. If it’s a unix based OS, you can run “top” to see the CPU usage; if you’re using a Windows based OS, I think XP has a similar tool. (Not sure about other versions of Windows.)

(Should I sign this PenisBull? Or perhaps DoggieTruth? Eh…you decide.)

The OP probably already knows this (if not, where did the cpu loading numbers come from?) but for anyone else who doesn’t know:

Windows has a display similar to “top” as part of the task manager. On win2k and xp you bring up the task manager by pressing ctrl-alt-del, or you can right click on the task bar at the bottom of the screen and select task manager.

Click on the processes tab and you will see all of the tasks that are running. You can click on the CPU column to sort them by cpu usage. Different operating systems handle idle time differently. Windows handles it by running the system idle task, so if your cpu isn’t busy, you’ll see the system idle task taking up a lot of time. This isn’t a problem. If the system idle task is taking 90 percent of the cpu time, that means that the cpu is only being used 10 percent.

There’s also a graph you can display under the performance tab.

On my computer, which is an 800 MHz Pentium III running XP, the normal cpu usage is hovering around 1 percent. When I open an explorer page and open google, I get a small spike that goes up to about 100 percent, but almost immediatly drops back down to 1 percent.

I would suspect spyware or a virus/trojan. The usual cures for such are a good anti-virus program, adaware, and spybot. While hunting through the task manager display, this link may be helpful. It explains what each task is, and includes many known trojans and bits of malware:


I vote for PenisBull.

Have you ever wanted an onscreen meter taht would allow you to see what your computer was doing?

If so, google WKrellM, and install that, it will give you a meter system that will tell you at all times what your CPU usage is. There is also another version called GKrellM. Try that one first as it is better (there is a windows version), but it may not work on your computer. It worked for a while on my computer, then I got a moden installed, and now it doesn’t want to work at all.