How do you change a screen resolution if it says ';Out Of Range';and you can't see the menu?

Very old computer that has windows 98. The screen is 24';. When you turn it on it only displays OUT of RANGE. Last night I was messing with the resolution size.It did this on the last setting I was checking out. I couldn't figure out how to correct it since I couldn't see the screen anymore. It went black and says ';OUT of RANGE';.How do you change a screen resolution if it says ';Out Of Range';and you can't see the menu?
when it boots hold f8 key to get boot menu. choose safe mode. when booted right click on desktop -%26gt; properties, and change the screen size to be the smallest. reboot.