So i got round to installing my gts 250 into my motherboard for physx with a gtx 560 running the display, however i want my gtx 560 to run the main display and the 250 for phys x but i cant find any way of telling my computer to use the gtx 560 as the main gpu.it seems if i plug the display port into the 560 and restart the pc nothing happens and if i go onto nvidea control panel i can't find a way of swapping it. the motherboard is an MSI z77a-g45