PCB Controller 2060-771640-003 for WD6400AAKS-00H2B0 WD5002ABYS-70B1B0
It's important to know when a PCB is bad and when swapping it with a donor PCB could work. A thorough diagnosis is required. Embedded in a Firmware on the PCB is "adaptive data" that is unique to the hard drive it's attached to.