Texas Instruments is not DELL.
The quite cheap adapters will blow up your dell frying everything or do nothing at all.
USB Signals are 5v and Firewire are 12v. Plugging 12v into a 5v device will not end well.
The dell community forum is not for support of 3rd party software or hardware.
Other than the Pixela Device there are no USB to firewire Devices in existence.