Hi
I have a new MACPRO 2.8 GHZ machine.
I've always used an extra PCI Firewire card in my old G4 Mac. Helped to capture video to ext Firewire drives as Mac's can't / don't deal with two devices on the same internal firewire bus.
From research there are two types of PCI-e card available that extends your Firewire capabilities on the MacPro.
One has a chipset that is designed / developed by SiiG and another that uses a Texas Instruments chipset.
If you do a Google search for "MaPro firewire 800 PCI-e card" you'll end up finding both, at various sites.
It's a little confusing at times as those sites that sell the card that uses SiiG chipsets say -> compatible with MacPro, but then qualify the compatibility by saying, often, not compatible with Quad Core Chips.
I emailed SiiG and they said that that any PCIe card you find on a site with the confusing info, will work in a MacPro 8-core mac.
In the end i went for this card as there is no confusion with any compatibility issues:
http://www.synchrotech.com/products-pcie/pcie-firewire-800_01.html
Anyway, I've installed this card and it works. I really wanted a card that gave me 3 x Firewire 800 ports, but it seems that 2 x 800 and 1 x 400 external ports is about the best you'll find on the market.
I've installed it in Slot 3 and I've installed a HighPoint RocketRaid 2314 ESATA card in Slot 4.
Anyway do a search and se what you can ind out there, mine works fine.
Chers
O