The DBX cards link multiple ADAM frames together and allow them to appear as one matrix in a given system. This makes it possible to increase the number of available users on a system by transparently integrating additional frames.

The DBX cards in all systems are wired such that if you could unplug the DBX cards with their port wiring intact and lay them out on the ground untangled, the DBX cards and the wiring connections would form a giant circle.