Good question. If you have a look at pics of the card it has a PCI-E connector located as follows:
An Asus one: top middle, just above & left of the fan click here / 5th pic on Newegg gives a better view/angle click here
A similar Inno3D one requires it too: top right click here
And the specs at Novatech (Specification tab > System requirements) click here states: "One 6-pin PCI Express supplementary power connectors"