Vizio L30 as a computer moniter

Gentlemen,
I hope someone would help me resolve a problem with my computer monitor. I am trying to use a Vizio L30 LCD monitor as the screen for my home pc without much (any) success. I can see the Windows screen at startup but when it tries to synch to the desktop it blanks out. My video card is a Radeon 9800 series and I am using the DVI input to connect. I've tried all the resolution settings that Windows XP Pro allows with any improvement. The monitor says that it prefers 1280 x 768 at 60 mhz but I still can't synch to the desktop. Any help would be greatly appreaciated.

Wendell Pahls