Wing Commander Fowler,
Not sure what you have, but it sounds like a pass through so you do not lose a USB Port by plugging in the Drive. If that is what you have, then it will not do you any good, and if you managed to plug in two ports for the drive, you will either damage it or completely mess up any data transfers.
Does the cable look something like this:
Now you would be much better off getting a USB 2.0 PCI Card for your comp. They are very cheap.
Take Care,
Richard