How to Change the Screen Refresh Rate In Windows XP

1. Click Start, click Control Panel, click Appearance and Themes, and then click Display.

Alternatively, right-click the desktop, and then click Properties. 

2. Click the Settings tab, and then click Advanced.

3. Click the Monitor tab, and then click the screen refresh rate that you want to use.

Watch it:
a. The default refresh rate setting is 60 Hertz (HZ); however, your monitor may support a higher setting.

b. Changes to the refresh rate affect all users that log on to the computer.