You will need some modifications then. The four pcie connectors can deliver 150w x 4 for a total of max 600w. A standard 4pin molex can deliver 132w per atx specifications. If you rely on the rumored 1.4w/GH, that would give your miner a maximum theoretical of 732w/1.4w = 522.85 GH. If you want more, you´re going to have to solder some extra 8pin pcie connectors in there somewhere.
Here I see 6 sockets in the PCB
https://www.kncminer.com/news/news-39These sockets are for Serial data (SPI probably), nothing to do with current. That specification 1.4w per GHs is actually KnC's weakest point, Bitfury proved <1w/GHs and HashFast & CoinTerra declared 0.6-0.7w/GHs.