> Can't think of anything else to try without a high speed oscilliscope.
Actually, I thought of one more thing to try. I switched to using the "nv" driver. When using the "nv" driver with ANY of the custom mode lines, the monitor reports a pixel clock rate of 156.93, rather than the 162.0 MHz that always appears with the "NVidia" driver. At first, I thought my custom mode line was working, but when I tried <Thunderbird's> mode line, the pixel clock was reported at 156.93 rather than the requested 161.0 MHz. So, for some reason, the pixel clock reported by the monitor is influenced by which video driver I am using (nv/nvidia), but not by the mode lines
Once again, it seems like a high speed oscilliscope will be needed to make any further progress .... Thanks, Scott.