What does this mean?
Dont parallel connected different DC input from different PSU into the same Hashing board.
It means you cant use two different power supplies for one S3
on the same board - if designed like the s1 it should have 2 boards. 1 power supply could work on 1 on the right and 1 could work on the left. However, it'd just be recommended to get 1 power supply that has enough pci-e connectors to do the job and power the miner.