I'm not sure what exactly went wrong, but after replacing my PSU the backplanes on my hotswap case went up in smoke, and I just found out it took all 6 of my HDDs with it. I can't see any scorching marks or anything on the PCBs on the drives, but none of the 6 drive do not spin at all or make any sound. I really hope it's just PCBs and all the mechanical parts are okay. Could the actuators or the motors be damaged instead?

Any how, assuming it's the PCB, a couple of quick questions. I learned up on what I have to do for PCB swap, but I've never don't any surface mount soldering. I found donordrives.com while googling, and they apparently do NV-RAM swap for you for the price of PCBs. They're price seems reasonable enough, but does anyone hear have experience with them? Also, if I could have somebody local do the soldering for me, I could just do one drive at a time, put new PCB then clone then next drive. I only need to recover 4 of the drives since they drives were in RAID-z2 set. Should I worry about reliabilities of the drives though? Should I just fix of all 6? Any advice would be appreciated. Much thanks in advance.

There is a chance internal components of your drives are affected as well.
If you need to recover only 4 out of 6 drives, then this is in your favour, because, well, some of the drives could have only their pcb affected.

Yes donordrives are trustworthy.

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Thank you for your input. How likely is that the internal components are damaged as well? I don't know if I should try to get hold of a PCB first to see if that's the problem first or just send the drives off to donordrives or the likes.

As far as repair shop goes, any other place besides donordrives that would do PCB swap for a reasonable fee? A place that could possibly repair other mechanical issues would be good. Thank you for the advices.

I suggest you contact member jono-ats from DataSavers (http://www.datasaversllc.com/). Jon will be able to sort everything for you for a fair price.

_________________
http://www.northwind.gr
SandForce SSD Recovery
Ransomware Reverse Engineering - NoMoreRansom! partners