Unfortunately, your chipset (945GM) has a hardware limitation in that it does not support hardware acceleration if the virtual desktop (as defined in xorg.conf) exceeds 2048 in one direction. This usually happens when you use an extended desktop side-by-side. A possible workaround is to place the monitors above one another. This bug is a duplicate of bug 146859.
Unfortunately, your chipset (945GM) has a hardware limitation in that it does not support hardware acceleration if the virtual desktop (as defined in xorg.conf) exceeds 2048 in one direction. This usually happens when you use an extended desktop side-by-side. A possible workaround is to place the monitors above one another. This bug is a duplicate of bug 146859.