DDR3 High Performance (HP) controller II supports single-rank, dual-rank and dual-slot Registered DIMM for Stratix® III and Stratix IV devices.
To support single-rank, you need to set "Total Memory chip selects", "Chip select per DIMM" and "Chip select per rank" parameters to 2.
To support dual-rank, you need to set "Total Memory chip selects" and "Chip select per DIMM" to 2. And set "Chip select per rank" parameters to 1.
To support dual-slot, you need to set "Total Memory chip selects" to 4 and set "Chip select per DIMM" and "Chip select per rank" parameters to 2.
Other combinations of these parameters will issue following error message in DDR3 HP controller GUI.
"Error: DDR3 Registered DIMMs only support single-rank, dual-rank, or dual-slot!"