When I do something that runs at 640x480, I get an "Out of Range" message that says: 29.4KHz / 60Hz. I assume it's resolution / refresh rate. The only way I have managed to use 640x480 is by installing a new driver for the video card, but when I turn off the computer it happens again. Monitor: LG Flatron L1918S. Can I force 640x480?