Turn off indexing service to see if it helps.

To turn off indexing:

1. Open up "My Computer."
2. Right-click on your hard drive (usually "C:") and choose "Properties."
3. Uncheck the box at the bottom that reads "Allow Indexing Service to..."
4. Click OK, and files will be removed from memory. This removal may take a few minutes to complete.

To disable the indexing service:

1. In the "Start" menu, choose "Run."
2. Type "services.msc" and press Enter.
3. Scroll-down to "Indexing Service" and double-click it.
4. If the service status is "Running", then stop it by pressing the "Stop" button.
5. To make sure this service doesn't run again, under "Startup Type:", choose "Disabled."

Also, like crosslink suggested, check your task mgr.