I was wondering if anyone else had problems plugging in the 24-pin cable into their AX850. My problem is with the end that plugs into the PSU (the end with two connectors). One connector is situated on top of the other and it seems the orientation is wrong compared to the PSU slots its supposed to plug into.
It may be in two pieces for convenience. Move the pieces around until the tab lines up and forms an integral 24-pin connector, then plug in the connector into the PSU and the other end into the motherboard. There will be chamfers to help with orientation.