If you want to apply the option “Adjust for best Performance” in the system settings, follow this guide

3 Steps To Apply This Tweak

Boost Windows 7 Gaming Performance with GameBooster

1. Step Hit Start

2. Step Enter “SystemPropertiesPerformance” into the search field, hit enter

3. Step Select “Adjust for best Performance” or at least uncheck the first two entries

This will give you a quick little performance boost.

For the full list of performance tweaks read this