The_Contractor - 10:35 pm on Aug 14, 2005 (gmt 0)
Looking at the specs of both your video card and the monitor/display I see the only supported resolution of the card that matches the display is 1920 x 1200 pixels. Your video card/adapter does not support the other resolutions of 1280 x 800 pixels or 1024 x 640 pixels (at least on the specs I'm looking at). Did you try deleting the monitors from device manager with your 15" hooked up. Then shut-down the computer and hook up the Apple display. Like I say, you'll have to run it at 1920 x 1200.
The video drivers are available via www.nvidia.com/content/drivers/drivers.asp under Graphics Driver>>GeFoForce and TNT2>> Operating System.