ReadyNAS NVX Failure - Lost Everything, Please Help

Important data especially irreplaceable data like family pictures should not be stored on just the one device. I would strongly recommend that you backup in future.

If it's just the PSU then the same procedure as for the NV+ v1 would need to be followed to rewire a standard ATX PSU if you wish to use that. However the NVX is a very old model discontinued way back in 2010. I don't think attempting to repair that unit would be worth it.

Assuming the disks are fine and that the RAID arrays are in a good state, and that the OS partition and data volume are also in a good state then migration to any RAIDiator-x86 unit, could be Ultra, Pro etc. should work fine. The NVX unit is a 32-bit unit. I wouldn't migrate from a 64-bit unit to a 32-bit unit but you'll be going the other way.

However the last of the RAIDiator-x86 units were discontinued way back in 2013 and there's no warranty for second hand purchases anyway.

You could get a new x86 model i.e. RN424, RN426, RN428, RN524X, RN526X, RN528X, RN626X, RN628X and follow this procedure: ReadyNAS: Migrating disks from RAIDiator 4.2 to ReadyNAS OS 6 (x86)

It is possible to use an ordinary x86 Linux machine to attempt data recovery if you prefer (at your own risk, of course). There are tools for Windows too, but those probably aren't free.

Important data especially irreplaceable data like family pictures should not be stored on just the one device. I would strongly recommend that you backup in future.