Comment 371 for bug 359392

The new release implements a workaround by default, which prevents the average needing to mess with xorg.conf to make the problem go away.

The flipside of this is that if you have already changed xorg.conf because your config is above average, Bryce's patch won't make a bit of difference.

I'm guessing your VirtualSize is already set to something over 2960 wide because you have a dual-screen setup of that size. Wonder if it's worth changing your VirtualSize line to 2960x2048 so both dimensions are over the magic 1600andsomething.