Processor usage constantly changing.

A friend is having trouble with a desktop PC. I don't have all the info yet but here is what it is doing. If you open the Windows Task Manager and look at
the CPU usage it goes: 2%, 4%, 75%, 99% or 100%, then 75%, 4%, 2%,
and repeats constantly in about 1-2 second intervals at each percentage. It does this with no programs shown running.

Is there something particular to look at when I go to get more information on it?

Thanks,

 

In Task Manager, click on the Processes tab and then click on the CPU usage column to sort by % of processor usage. This will tell you what process(es) are causing the jump.

Is the unexplained jump in CPU usage resulting in any symptoms such as system freeze ups or slow performance? If not, I wouldn't be overly concerned about the issue unless symptoms develop.

Although this is not a complete list, here are a few of the things I've run across that can cause the CPU usage spikes you're describing:

* Certain antivirus programs (such as versions of Norton and McAfee).

* Two or more avtiivirus programs running at one time. In layman's terms, each thinks the other is a possible virus; this slows down the PC.

* If you get extended (<15 second at a time) CPU spikes to 100%, this can sometimes be a sign of either a corrupted Windows install or an impending failure of the hard drive.

Hope this info. helps.