Just bought a new 22' LG monitor and I have the Mini DisplayPort to VGA. When I connect my monitor to my MacBook all is OK until I try to chose the 1680x1050 which is the LG's prefered resolution. When I chose it, my monitor turns to black, then after a while it shows the picture for a second, then black again.. Is this a 9400m fault, or the VGA adapter fault? If I try a MiniDisplay port to DVI, will it work in 1680 x 1050? All the other resolutions are shown ok..