FA-101 issues PLEASE HELP!!!! :)

Hello all,
I recently took up a friends request to help get their recently purchased FA-101 Firewire interface to work with the computer they use for recording. 
They are using a DELL XPS 400 with Windows XP SP3, not a very good box but nonetheless I wanted to help.
 
Here is the run down. When they purchased the Edirol interface they also purchased a Texas Istruments Firewire card so there shouldn't be any issues. Upon starting up the drivers install perfectly, or so it seems. No hardware errors, "device is working properly" yada yada.
 
When you go into Control Panel>Sound, there isnt an Audio Device on the Input/Output showing up, but if you go into Device manager under Hardware you can see the "edirol FA-101" in the device listing.
 
After HOURS of frustration and reinstalls of the driver, I gave up and decided to pick up my Recording PC and and give it a try just to rule out a hardware issue. Long story short. Hooked mine up, installed the firewire card from the problem computer, installed the drivers and sure enough it shows up in Windows devices as a selectable I/O device, and then I confirmed in SONAR 8.5 that it was also selectable in "audio" properties. I even recorded about 5 mins of there live session to make sure that aspect worked as well. Im using Win 7, different OS, but I was able to rule out hardware.
 
 Then I then told them I'd call Roland and see what they thought. "reinstall the OS" pretty much summed up the convo, so reluctantly I did... to no avail with a fresh Windows XP Service Pack 3, the Edirol FA-101 will not show up as a valid I/O device STILL!!
 
I dont think ive ever had an issue as frustrating as this... Please if anyone can shed some light or has some suggestions I'd really appreciate it.
 
 

Chappel thats for reply,
 
What it boils down to is, in order for the FA-101 to be able to be used in SONAR, it would need to be seen within Windows sound properties, as a valid audio device, from my dealings with various Audio recording software.
 
Unfortunatley, its not even showing up in Windows, thats where im stuck.
 
Ive installed this device on my rig running Windows 7, and it shows up in Windows and within SONAR 8.5. So ive determined the Interface hardware has to be working properly. But on the other computer, Windows XP pro, service pack 3, DELL XPS 400, it wont register even within windows.
 
 All drivers FA-101 Sub1, Sub2, and the Edirol FA-101, say that they install fine and that the device is working. But Oddly it wont show in Windows Audio i/o device, nor can I get it to work within SONAR. Ive disabled the Sigmatel Audio within BIOS as well.
 
 Another question is, since the Edirol FA-101 driver is showing up in Device manager>Hardware, is there some way to enable it within SONAR? Ive gone thru the "Audio" properties and cant find the driver in the driver profile section (again, if it isnt showing up as a valid I/O device in Windows, would it even show in SONAR?)
 
Thanks