Its a molex connector going to the monitor not a vga cable for those that asked.
That explains things. From the screen image you described it sounds to me like you have a STD res monitor in your cab. My cab has a D9400 in it so I run my monitor at 800X600 for everything. You can google EDID dongle to see what they are but as for where to get one, I have no clue.
From what I've read online the 8 series of nVidia cards wont go into those lower screen resolutions without this dongle.
Matt