I am looking to install this Firewire Card which SIIG confirmed is compatible with the new Mac Pro:
www.bhphotovideo.com
It says this in the instructions:
Note: The 4-pin power connector is designed to provide additional power to the board when needed. This connection is optional. However, we recommend to connect this power connector when the following conditions occur:
- All ports are used.
- Device(s) not being detected.
Where would I connect this power connector?

SIIG 3-Port FireWire 800 PCIe Adapter
Buy SIIG 3-Port FireWire 800 PCIe Adapter featuring Texas Instruments TI XIO2213BZAY Chipset, 3 x External FireWire 800 (1394b) Ports, Installs in Any Available PCIe Slot, Hot-Swappable, Onboard Power Connector, FCC, CE Certified, RoHS Compliant. Review SIIG null

It says this in the instructions:
Note: The 4-pin power connector is designed to provide additional power to the board when needed. This connection is optional. However, we recommend to connect this power connector when the following conditions occur:
- All ports are used.
- Device(s) not being detected.
Where would I connect this power connector?