The biggest deal about these 2.048 Vortex 2 drivers, and a big selling point for Vortex 2 boards against other cards like the MX400, is that the new drivers include support for the new A3D 3.0.

This explains why it took the drivers so very long to arrive - they were originally billed as just adding EAX support, which wasn't such a big deal. Enthusiasts were irked and puzzled by the late delivery of the new software. But the A3D 3.0 update includes considerably more features than the fans were expecting.

The original A3D 1.0 is just positional audio, with no environmental frills. It can easily be emulated by other cards, including the MX400, by turning A3D calls into DirectSound 3D ones.

A3D 2.0 added occlusions and reflections, from accurately geometrically rendered surfaces, and also had environmental sound modification. This lets A3D 2.0 supporting games properly change sounds when you're meant to be underwater, for instance.

A3D 2.0 also added "A2D", the software-only reduced version of A3D 2.0 that works on any old sound card, but at the cost of a big fat performance hit. You can use A2D with the MX400 and get results no worse than those from any other sound card, because all of the work's being done by the CPU.

A3D 3.0 adds volumetric sound sources, which work like Sensaura's ZoomFX; you can have a great big crowd or babbling brook or train that emits a sound from its entire volume, not just from particular points.

A3D 3.0 also lets games play MPEG 1 Layer 3 (MP3) compressed sounds as positional audio sources, as well as supporting the usual uncompressed sound formats. This isn't necessarily a great idea on slower computers using current sound cards, without hardware MP3 decoding. But recent machines can take MP3 decoding in stride, even in games, quite comfortably. And the super compression offered by MP3 means something like ten times as much sound can be packed into a given amount of disk space.

The EAX reverb support in A3D 3.0 is actually a fall-back setting, for games that specifically want to use EAX or don't work with A3D 3.0's own geometric reverb system. The A3D 3.0 reverb seamlessly falls back to I3DL2 or EAX reverb when it's not supported.