Wheres my firewire card gone ?

Well, tried to transfer some video from my DV camera to my PC. Mysteriously my PC is not detecting my Video Camera, it was last working about 3 weeks ago. Went into control panel to try an analyse connected hardware - no joy. I can't recall where my firewire card install cd is...

any suggestions for a firewire card testing utility?

Regards,

BPlotter