You can try searching for a circuit board on Ebay. This might help explain a bit about the boards http://community.wd.com/t5/Off-Topic-Discussions/Bridge-Boards/td-p/353839 and this https://wdc.custhelp.com/app/answers/detail/a_id/70/session/L3RpbWUvMTM5MDMyNjIwNS9zaWQvZVBrTU9YS2w%3D
Joe