-The EPCI-DC is a two bus card, but it has two internal connectors. One is part of bus 1 and the other is part of bus 2. If you have drives on the external port of bus 1, and drives on the internal port of bus 1, then the last physical drive on the external port AND the last physical drive on the internal port must both be terminated. It's all one chain. The same (obviously) holds true for bus 2.
Note:
-If the drives are LVD, they will not have internal termination jumpers. Therefore, if an LVD drive is used on the internal bus, a terminator must be attached to the last physical node of the internal cable.
-If no internal drives are used, the ATTO card will self-terminate if termination is set to "Automatic." It should also self disable if both the internal and external connectors are in use if set to "Automatic." It may be necessary to disable termination if both internal and external connectors are used if for some reason the Automatic setting doesn't behave properly.