I believe the board you are talking about is the old VX board. I am not certain what they used for USB.
I do remember their TX boards though, amd they used a custom setup. The USB cable went to a small card that had the ports on it. That card had more on it then just the ports though. We had a customer bring in a standard USB adaptor and tried to get it to work with the board but never got it to.
I would expect that the older VX board would use the same thing as the "newer" TX. You might be better off just getting a USB card.
S.