To disable Content Indexing on a disk.
1. Click Start – Computer.
2.Right-click the disk (say c:) and select properties.
3. Uncheck “Allow Files on this drive to have contents indexed in addition to file properties“.
4.Click Apply and OK.
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You will be asked a option and select "apply to c:\folders and sub folders"
later if u get any messages regarding privileges click on "continue" and then "ignore all"
reboot your system...u will see a noticeable change in the performance..
Feel free to comment.