RP,
It may simply be that you haven't got the right driver for the PCI USB card, so the O/S is seeing it as 1.1.
It may also be a BIOS setting that needs adjusting (although that would be more likely with integrated USB ports).
I recently installed a Belkin 4-port USB 2.0 card in a 6 year old Compaq Deskpro, so I'd be simply astounded if this card didn't work in a 2-year old PC.
Just a thought - does your PC already have some USB 2.0 ports? I'd have thought that a PC that new might well have.
SD