For the 4U chassis SC846E1-R1200B with the X7DWA-N motherboard and controller AOC-USASLP-H8iR, which cable is needed to connect 24 drives to the HDD controller card? How many cables are needed? There are three connectors on the blackplane, but do all three have to be connected for the 24 HDDs to work? There are only two connectors on the controller.
Just connect one ipass cable from controller to J0. J2 is only for cascading. You can use the cable CBL-0281L (iPass to iPass 75cm PBF).