Can someone help identify these caps?

[phlegeton]

Thanks for this. Maybe a stupid question, how can I measure the voltage. When the drive is in chassis, I can't reach it.

[fzabkar]

Attach the PCB to the PSU in a desktop PC?

[phlegeton]

I only have to power up the pcb, and the drive doesn't have to be attached? In that case, I could also use my lab power supply. I have a SATA power cable, I attach picture of it. If I can use that one, that would make things much easier.

[fzabkar]

Yes, all we're doing is confirming whether the 5V supply is being cleaned up before it gets to the preamp. In fact, just do a continuity check. That should be enough. No need to power up the drive.

[phlegeton]

I wasn;t sure if the drive needs to be connected for load. I checked, and yes, there is continuity between the +5V and the 5V e-fuse.

[fzabkar]

I wasn;t sure if the drive needs to be connected for load. I checked, and yes, there is continuity between the +5V and the 5V e-fuse.

I'm wanting to know if there is continuity between the output side of the e-fuse and the HDA connector. That will tell us if the preamp's 5V supply is being protected (and filtered?) by the IC.

[phlegeton]

Yes, there is continuity between the output side of the e-fuse and the HDA connector.

[fzabkar]

At this point I don't know any more than anyone else. Your drive has more than the usual protections, so it's hard to see how a bad PSU could be responsible for all those uncorrectable errors. But I'm no expert. :-??

[phlegeton]

Well, you do know more then anyone I ever met about the electronic part of hard drives. And I'm very thankful for your help and patience. And we can now rule out power supply issues. The question is then.. was this just a fluke? Or the OS which runs on the NAS, had a mind of it's own? Or the SAS controller? When I think about the SAS controller, I start to think about the lanes. That would be very hard to debug, or troubleshoot. I'm not sure if I want to dive into that rabbit hole.

[fzabkar]

When you have a lot of drives in a rack, their mutual vibration can cause tracking problems. However, your PCB has a shock sensor at two corners (the white angled components), so the firmware would have rotational vibration compensation.

https://www.hddoracle.com/viewtopic.php?p=19489#p19489

I really have no explanation for your problems. That said, if you can retrieve a SMART report, then this means that the drives can still reach the firmware zone (System Area) on the platters. In fact, the SMART logs may have more detailed error information. You could use smartctl (Linux) or GSmartControl (Windows) to dump these logs.