The card is equipped with three connectors for display devices: two DVI-I ports and one HDMI.
The former two are connected to the Master GPU and can be used simultaneously in SLI mode whereas the latter is connected to the Slave GPU and can only be used when not in SLI mode.
This odd solution actually negates the value of the dedicated HDMI port. For comparison, this port of the GeForce 9800 GX2 was connected to the Master GPU together with one DVI-I.
What is the porpoise?
There has to be some kind of logical explanation.