Swapping platters much are more risky than changing heads. What is why price for changing heads and swapping are so different. Like example my price for changing heads starting from about $100 and price for swapping platters starting from $900.

why you want to swap platter BTW . I swap platter on those models where spindle motor does problem . Platter swap is bit difficult job and needs good experience even with good tools . I am sure in your case there is no need for platter swap . 1st you check if there is FW problem then you go next. you can start in this way 1st Swap PCB , 2nd check FW ,then go to heads after these or during these steps if you find any change in clicking you check FirmWare. one more thing faulty heads and FW problem both are having different sounds. i recommend you to see a local DR expert if the data is important and if there is no data then carry on playing with platters lol.

Thank you mad4hdd for your recommendations, let me summarize the steps already doing and why:
1) I use this hard drive to back up all my pictures, videos and other personal files, connected to an external dock on my laptop one day Win7 have reported me record as being in RAW format, I tried Test-Disk without success or increasing the problem.
2) The disc rotates normally but is not recognized by Win7, and on my desktop it's seen in the BIOS but gives errors in the SMART.
3) I order the same disc with the same PCB, I swap PCBs, same problem, I put the circuits as the original place and disconnecting the SATA cable (PC running) the PMos burn!
4) I de soldered the PMos and checked if the preamp look Ko, it seems not.
see photos on bottom.
5) I Hesitate to swap again PCBs, how to be sure that the preamp is Ok?
Thank you ! For your support.

You are welcome. As you told , initially your drives was with SMART error and was not showing in Windows but was detecting in BIOS . Right ? Was also asking for format ? Now tell me one thing have you opened media ? If not, then don't open it . 1st you fix your PCB problem then if drive detects well then try RAW recovery . On starting stage drive was spinning up fine and there was no sound . my dear there was no problem with your heads and platter. hope still no problem with heads . I hope you have not opened media( head,platter etc) best of luck

Hi mad4hdd, No I've not opened yet the drive, I'm waiting for PMos for replacement then restart to see if it's burn again or not and if (hopefully) not see what appends on my desktop. The last trail indicate know on BIOS but SWAT error when booting on Win7, I've removed auto-swap-detection on Bios then we will see ... When you say "RAW recovery" could you tell me more please ? Thanks.

This is where the preamp measurement should be taken:

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A backup a day keeps DR away.

Hi & thanks fzabkar for the information, I'll check the -5V after PFet replacement and let you know.

I would first measure the resistance between that point and ground. That will tell you whether the preamp is shorted.

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A backup a day keeps DR away.

Hi all, I'm back. To answer the question from fzabkar I compare to GND with
ohmmeter on the point :
1: Hot on the point => Measure = 0.676 on 2Kohm range on HDD OK.
2: Same -----------=> Measure = 0.629 ---------------------- KO.
3: Hot to GND => Measure = 1.039 on OK.
4: Hot to GND => Measure = 1.036 on KO.

Then I put the drive on docking station without USB connection, only power supply, on the Good HDD I measure -5.20V and 0V on failing one.
Note: The PMos is not in place on failing, I'm waiting to receive it ....

It looks the preamp is not shorted, what do you think ?

ISTM that the preamp is probably OK.

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A backup a day keeps DR away.