Hello,

Below is my seagate HDD details.

PCB Number: 100466824 REV B
VCM Controller or SMOOTH CHIP number: 100439116
MCU or Big Chip: TTB5501D

Card was burnt due to SATA connector cable problem. Wanted to do PCB replacement.

Got 2 PCB cards which is 1:1 match for the above specs, the HDD doesn't run at all. However if i put new 1TB card the HDD spins properly which proves no motor issue or anything.

HDD runs when I put other mismatching PCBs but when i put the exact match the HDD doesn't run at all. What seems to be the problem with the HDD ?

Note: When i say run - it means the motor spins up and everything, it ofcoss doesn't get detected in BIOS or anywhere.

We also did the Flash chip transfer from patient to donor too - No success there.

I think you have to learn first how Seagate drives work.

The problem is now not only on the PCB but a little deeper inside the drive (BIG hint). The new PCB, despite the fact that is working, is finding something that he doesn't like.... and refuse to start. And it is probably telling you this! You just have to.... listen.