I'm not an expert on soundcards, but I think BlindDog's is sound advice. ASIO seems to be the key to zero latency.
I have an RME Hammerfall 9632, which is also an ASIO card, and the responsiveness is instant. Playing from the ultrafast keyboard of my Mg works perfectly with the Arturia synths using that.
BTW one thing to watch with soundcards at this level is the kind of output they do. I originally bought a 9652, which only has digital outputs, only to realise that I needed the 9632 with analogue outputs.
Actually I think we need to combine our knowledge of soundcards, because they're an essential part of getting the best from the Arturia synths. I learned the hard way, and my knowledge now is still sketchy. I got something that's perfect, but I know I don't have the knowledge to say much to someone else apart from "I know this one works" and "look for ASIO."