Nvidia is a chipset maker that supplies to companies like MSI, Leadtek, BFG, Chaintek etc... ATI is a video chipset maker and their chips end up in ATI brand cards, Sapphire, Powercolor, Rosewill etc...
Unless there was some flaky deal that I have never heard of - you will not find ATI on a NVidia video chipset card or box, unless there is a comparison on the box.
BTW ATI makes excellent chipsets, I just happen to prefer Nvidia at the moment.