monitor sync problem

[discarnet]

ok first of all I appolagise if this is in the wrong forum

I have a couple of games that will not run on my monitor the sounds work ok but the monitor displays a black screen with the follow message

SYNC OUT OF RANGE

166.0KHZ 240HZ NN

I have tweeked grafix card (nvida fx5200 128) and adjusted screen res and size but still wont run games.

These are both brand new games.

does anyone have any ideas for a work around on this