"Malcz86" <Malcz86@discussions.microsoft.com> wrote in message
news:9E884A68-EBBD-4ED1-A453-2E5D7487B55F@microsoft.com...
> We've had this problem quite a lot on XP and it was todo with a graphics
> chipset control panel option which overwrites the windows settings after a
> reboot. If you want the change to be permanent you need to setup the dual
> monitor in the chipset control panel.

I have used many dual-head XP systems over the years, but have never seen it
happen, with Matrox, ATi and nVidia GPUs. I have seen it happen on the only
two Vista dual-head systems that I have used, including my own. It does not
happen on that same computer when booted into XP. I also cannot remember
there ever being a way to choose which monitor is primary either (ATi FireGL
and nVidia QuadroFX) on the Vista drivers.

ss.