The Windows Experience Index measures the capability of your computer’s hardware and software configuration and expresses this measurement as a number called a base score. If you have installed a new piece of hardware like a GPU unit, then you can force Windows 7 to re-run all the tests and rebuild the Windows Experience Index. Here is how you can do this :
- Open Control Panel and choose the Small icons view from the dropdown list at the top-right.
- Click on Performance Information and Tools from the list.
- Click on the Advanced Tools shown in the left side.
- Click on the Clear all Windows Experience Index scrores and re-rate the system link as shown.
Windows will remove all your previous Windows Experience Index scores and start a new series of tests to re-rate your system. After the tests are finished, you will be shown the new score of your system.