I'm not sure I understand the problem. Is the card recognized by the system? Or does the driver for the card only get loaded when a FW peripheral is attached to it?
Firewire's pretty old, so I would think a 2004 machine wouldn't have any trouble with a Firewire add-on card. I doubt it's the BIOS, myself, but I've not experienced this problem.
It seems that some newer PCs don't supply the 5V that some Firewire cards require.
http://www.techsuppo...t-recognised.html
Sometimes trying a different slot seems to help (if that's an option) - http://www.techsuppo...tect-install.html
HTH a little. Good luck.
Cheers,
Scott.