This is one of those fabled performance tricks told over the years: moving your system’s paging file from the C partition to a separate hard drive gives you a nice little performance boost. I’ll let you google up about the whys but here is how to do it.
Open Control Panel -> System -> Advanced System Settings. Choose the Advancedtab and click on the settings button of the Performance category. In the popup, click on the Advanced tab and finally the change button. Uncheck the solitary checkbox and create a new page file in a different hard drive after selecting the No paging file option for the C partition.