QNAP TS-1232XU with 32GB RAM

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Hello

Regarding the warranty, my units warranty has expired, so it's not a problem.

There should be quite a few who own a QNAP TS-*32XU NAS and there should be an interest in upgrading from the maximum 16GB UDIMM (according to QNAP's spec) to 32GB which should work with the 64-bit "AnnapurnaLabs Alpine AL324 ARM® Cortex-A57 quad-core 1.7 GHz processor".

Are any of these DDR4 variants better or worse (bold = requirement from specification):

• 2400MHz PC4-19200 versus 2666MHz PC4-21300
  
• Single Ranked (1Rx8 faster) versus Dual Ranked (2Rx8) - bit-width x8 is far superior to x4
  
• ECC (Error-Correcting) versus non-ECC (non-Error-Correcting)
  
• UDIMM (Unbuffered) versus RDIMM (Registered)
  
• Single-sided (RAM soldered to one side) versus Dual-sided (RAM soldered to both sides)
  

Have been looking around for single-channel memory modules with the specification 1x32GB DDR4 2400MHz PC4-19200 UDIMM 1.2V 288-pin but cannot find one with this exact specification from manufacturers Crucial, Kingston, Corsair or G.SKILL.

Questions:

1. It is hard to find anything slower than 2666MHz PC4-21300, is that doable, will it work?
   
2. All I have seen seems to be 2Rx8, I assume that is fine?
   
3. ECC or non-ECC, does this matter, should I choose one over the other?
   
4. It should not matter if it is a single- or double-sided module, can you confirm?
   
5. Could you please help and advice where to find a UDIMM memory module that could work?
   

Thanks