How do I change the Display Frequency on linux

Question

I want to change the display's frequency from 60hz to 50hz, on a fedora core 9 box, anyone know how to do this?

Thank you

Answer 1

Expand the Monitor section of /etc/X11/xorg.conf to look something like this:

Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Monitor Vendor"
        ModelName    "Monitor Model"
        HorizSync    30-107
        VertRefresh  48-120
EndSection

Answer 2

Add a new modeline to the Monitor section of /etc/X11/xorg.conf with the desired frequency. Use cvt to generate the appropriate modeline.