SVCHost using 100% CPU in Windows 7

I am having a problem with Windows 7. When I boot up, the CPU jumps to 100% execution for about 10-15 minutes. During this time, it is really slow, and if I play any music, the songs play slowly and sound distorted.

I tried to scan my computer with different antivirus programs, I used Spybot, HijackThis, and CCleaner, but I didn’t find anything of note.

I watched the process list in Task Manager and saw that there are two processes that are to blame. There are two copies of svchost.exe, one using ~48% CPU, the second (under the Network Service account) using ~37%. For the first 15 minutes, the CPU runs at about 70-80%, then eventually drops to 30-40%.

I don’t know what to do. I could not find a way to stop the services, and if I try to kill them, sometimes the system crashes.

You are on the right track with your investigation. The problem is that you got stuck at svchost.exe. The catch is that svchost is a generic process that hosts multiple services. What you need to do is to figure out which service that it is hosting is sucking cycles.

1. Get Process Explorer (and run it; of course)
   1. Right-click on the column header and select Select Columns…
   2. Under the Process Performance tab, make sure that CPU and CPU History are selected
2. For each instance of svchost.exe with high CPU usage,
   1. Double-click it
   2. Switch to the Services tab
   3. Click one of the services and click Stop
   4. Look at that CPU graph of that instance of svchost to see if it has gone down
   5. Goto 2.3 until you see a statistically significant drop in CPU usage for that instance
   6. Note down what the last service you stopped was
3. Examine the service(s) that were causing high CPU usage to see if they can be disabled, updated, removed, etc.
4. Figure out why the system idles at 30-40% CPU usage