Change display resolution in Linux

To change the VGA card display resolution in RHEL5

1) First check all the possible resolutions supported by your graphics card using the following command.

            "xrandr"

It will display all possible resolutions.

2) Change resolution.

Suppose your graphics card support 1024x768 resolution then you can change it using the following command.

"xrandr -s 1024x768"

If you don't have "1024x768" in that “xrandr” output, try below one this might be help to get “1024x768”.

In “/etc/X11/xorg.conf” file just check the entries

            SubSection "Display"

                        Viewport  0 0

                        Depth     24

                        Modes "1024x768"

            EndSubSection

Check the entry “Modes”. If it is not present just add this line and check.