Refresh Rate Hell (SaX2)

Since having purchased a Geforce FX 5200. my refresh rate has miraculously 'changed' and I can no longer get a GUI. I have tried to use SaX2 to change it, but SaX auto configures my screen to a refresh rate of 74hz which is 14 hz over what it will allow, thus my TFT flashes "Over Range" in my face. Anyone who knows a method of rectifying the problem without starting up the GUI (obvious reason) would be much appreciated. P.S: I will just add that I am using a Natcomp TFT (obscure model :-( )