So is that the same breakaway cable the X360 uses? I have several of those and they can be found on ebay.
No, original xbox breakaway cable is different from the 360 breakaway cable. Also the redoctane dance pads that had USB PC support had a PS2 and original XBOX connector. However, it came with two breakaway ends for the xbox cable; A standard xbox connector and a USB connector. You would swap the xbox breakaway connector for the one that has a USB end, which would then plug into the computer. So in simple terms, it had a PS2 connector, and the xbox breakaway which came with two cables, a standard xbox and a USB.
You can't just buy these cables, as they were pretty much made only for this device. You can, however, purchase a XBOX to USB adapter, and then just plug in the standard xbox breakaway cable into that adapter and it should work exactly the same.
http://www.ebay.com/itm/121240122512?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Check out my website:
http://thecyberquake.weebly.com/