NVRefreshTool not working at 1280x960

[Rebel7254]

I have Win2k and a G4, so I have to deal with the gaming refresh rate issue. Well, all works fine at every resolution I've tried, except 1280x960. It always wants to go to 100 Hz, and that makes my monitor display wavy lines really bad. I try lowering the setting in the RefreshTool to 85 Hz, restart, and when I get back into windows it goes back to 100 Hz. What's the deal here?