Greetings from 5 years later
that particular Dell cable won't work dual port, it doesn't have all 29 pins on the SFF 8482 side.
Also windows 10 doesn't support MPIO (aka dual port) at all. it's for server versions of Windows. A guy on Dell forums allegedly hacked a way to make it work but I didn't try downloading his custom drivers and registry hacks.
that particular Dell cable won't work dual port, it doesn't have all 29 pins on the SFF 8482 side.
Also windows 10 doesn't support MPIO (aka dual port) at all. it's for server versions of Windows. A guy on Dell forums allegedly hacked a way to make it work but I didn't try downloading his custom drivers and registry hacks.