well.. yes.
you have to connect 1 end to the card and the other 2 to the PSU.
if you want to Oc the card, its reccomended you put those 2 plugs on different rails on the PSU.
if youre not Oc'ing, you can connect tem to the same one.
( i reccoment connecting both connectors tough... because if the not connected on hits the case, it might short your card or PSU.