My guess is that the ATI card doesn't support CUDA and you don't have OpenCL installed. You'll probably have to install OpenCL to mine on an ATI card.
I'm having some issues. I was mining with a 560 Ti using the CUDA miner. I added a ATI 5750 and it wouldn't show. I can't get the miner to show the 5750. Any ideas?
I have the newest Open CL installed. I tried a earlier version and I get an error message that says "The display driver installed on this system does not have OpenCL support for AMD GPUs" I have the AMD driver installed.
Now my 560 Ti isn't showing.
![Huh](https://bitcointalk.org/Smileys/default/huh.gif)
Ok if I unplug my GTX 560 Ti and put my display on the 5750, the 5750 appears. I can't get both to appear though.