The soundcard being "NVIDIA" smells like the integrated NVIDIA soundcard embedded in some PC chipsets developed by NVIDIA for Athlon systems.
Although it is usually fine in games (sourround sound etc), it's probably not the best solution for a pro soundcard. As for ASIO drivers, you can try the ASIO4ALL drivers (do a google search on that) which provide ASIO capabilities even for soundcards that have no manufacturer's ASIO drivers, like older Crative SB Live cards.
The guys in this forum can guide you about pro soundcards