Signal Out of Frequency Range Message During Boot

Had to change my monitor and now I cannot see the boot screen. As soon as booting starts I get the captioned message and no screen until booting has been completd when I get my normal desktop.

Question what sets the screen resolution etc during the boot process and how can I adjust it please?


Problem Solved. The boot resolution is set by VGA setting in kernel but that was not the problem. I am using a AdderLink KVM remote and it needs to be restarted after monitor change or OS does not detect the new display.