Could you tell me why you chose to use the Nvidia to connect to your tele?
A better result on Win7 would be to remove the Nvidia and connect the Monitor and the Tele to the ATI...
The Nvidia is an older generation card it's DX9 support and the ATI is DX10.1 why use the Nvidia all together?
and is you really want it to be of some use you can connect you monitor to it and just let it be the card for your rig
But the ATI makes up for the Nvidia GPU, so why don't you just remove it and use a single GPU?