I'm using a GeForce4 ti 4600 and a PCI Vid card to run dual monitors at the same resolution. Both drivers are the latest ones. I've tried rolling back as well.
What happens is any open application on monitor #2 gets pushed right 1/5th of the way off the right side of the monitor. When I am playing a game on #1 I will turn right (towards monitor #2) and it will minimize my game.
