Seagate 7200.12 PCB swap
I fried my old PCB and found a new PCB on ebay with the exact Series number and P/N number (including same firmware). When I boot it up though it wont show up in bios and it keeps doing a bad data read noise (when the head hits the middle to reset it). Anyone have any idea how I could make this work? It is a ST3500418AS, P/N 9SL142-302
Most modern HDDs store unique, drive specific "adaptive" information in a serial EEPROM chip. This chip, or its contents, needs to be transferred from patient to donor.
The following PCB suppliers offer a firmware transfer service, either for free, or for US$10:
I would advise that you avoid those suppliers who don't tell you that a board won't work without modification. Often they will attempt to obscure the requirement for a firmware transfer by deceptively describing their products as being "for data recovery only".
Alternatively, if you are not adept at soldering, your local TV/AV repair shop should be able to transfer the chip for you.
Onepcbsolution.com also offer a firmware transfer service for US$20 if you have purchased your board from a different supplier:
Depending on the fault with your PCB, sometimes there is an easy no-cost DIY fix. Were any of the following components damaged?
If so, see http://www.users.on.net/~fzabkar/HDD/TVS_diode_FAQ.html
Send it to these guys, I was very pleased with their service and was able to recover my drive: