HTPC Antec Fusion Remote Case

Hi
I am not sure if I am posting in the right forum, please feel free to sugest a better forum.

I have an Antec Fusion Remote casethat I am setting up as a HTPC and a Zotac ION that has an external power supply. The problem is there is a 3 pin lead that comes from the power supply, joined in to rear of the ATX plug and connects to the VFD/LCD panel on the front of the case. Problem is how do I connect this in the motherboard so that VFD/LCD panel works.

I will not be using the ATX power supply as there is no ATX connection on the motherboard so I need to find an alternative way of connecting. The wires from the ATX power supply connect to the 5v, Gnd and 5v_Aux on the rear of the ATX plug. Any suggestions would be gratefully received.

Thanks in advance,
Di