Service pack 1 should recognise the hub, if it's connected by a USB lead to the motherboard. If you are connecting a PCI card, then you may need to install the drivers for the card first.
If you do need to install the card/hubs own drivers, then do this before installing the hardware.
I think the 5th. internal port of the card will be to connect to a front faceplate on the tower to give one port at the front j.