You will need hacked/patched nvidia and nvidia physx drivers to run both those cards on that mobo.
You need to look for article that say ATI and PhysX.
It's quite a tiresome process and really fun when it works
, but then updating the drivers again becomes a pain.
Here are a fewhttp://www.tomshardware.com/news/nvidia-physx-ati,5764.htmlhttp://www.overclock.net/graphics-cards-general/508305-howto-ati-nvidia-physx-guide.html