If the customer is considering using a bus converter to drop say 24V or 48V from the AC/DC power supply, one must calculate the power that all four FPGAs will demand. POL #3 is supplying 1.5V, 10A and looking at the pink curve shown here (12V input) at 10A the efficiency is approximately 87.5%. This calculates at POL #3 requiring 17.14W. This step is repeated for all four POLs on the card, the power requirements are added together to equal 52.2W, which means the bus converter needs to supply a minimum of 4.35A.