Re: ALSA and GTX 4XX Series
The /dev audio device files are related to the kernel ALSA driver, not the NVIDIA graphics driver. Depending on your distro, the files may physically be created by udev or similar. While there are some interactions between the ALSA driver and the NVIDIA graphics driver (e.g. to pass EDID information from the monitor to the audio driver), none of those interactions should be able to cause /dev files not to be crated, since they happen long after the device files would be created.