Seagate ST3750640AS SATA 3.5 PCB - 9BJ148-621 (3.AHG / 100419004 D)

Sale is for the hard drive circuit board (PCB / logic board) ONLY — the hard disk is not included. Because we have a large inventory, the PCB you receive may differ slightly from the photo. This board is intended for use in HDD repair and data recovery efforts. Before ordering, follow our hard drive diagnostics guide to confirm a PCB swap will address your problem, and review the Donor Matching Guide to ensure compatibility. Most Seagate PCBs store unique calibration and firmware data in a ROM "memory" chip; that data is required for correct drive operation. The ROM chip itself or its contents must be transferred to the replacement board. If you cannot perform the transfer, a local computer technician can usually move the chip for you. For purchases of $60 or more we include complimentary adaptation service, which covers either transplanting the ROM chip onto the new PCB or reprogramming the replacement board with the correct ROM data. If a plain PCB swap does not resolve the issue, we also provide a full PCB Replacement Service — see the Adaptation Service page for complete details. If you plan to do the work yourself, consult our PCB Replacement Guide for step-by-step instructions.