To change the grid color of the  graphs, perform the following steps:
Choose EditPreferences. The Preferences dialog is displayed.
Select the Resource Monitor tab in the Preferences dialog.
Click on the Grid color button. The Pick a color dialog is displayed.
Choose a color from the Palette, or use the color wheel or the spin boxes to customize the color.
Click OK to close the Pick a color dialog.
Click Close to close the Preferences dialog.
