I'll try and find the box an get back with details, but these headphones worked perfectly with Vista 64.
EDIT: Here we go;
24 bit SE, SB1394.
I just upgraded my daughters computer and put a Creative SB 5.1 VX card in, a much more recient card than I have, I think I'll swap them as she is using only two speakers. This card plus new drivers may help although the problem seems to be with Windows 7 not allowing the headphones to work properly unless set on default.