Low Power NAS only - your hardware suggestions please

Encouraged on Reddit to ask my question here, so here it is:

Hi all

I want to build a small NAS mostly for file sharing and backups.

The things I consider absolutely necessary:

  • Lowest power usage possible
    
  • Highest write/read speeds in LAN possible (1Gbps LAN)
    
  • Small size, needs to go in a tight space, so as small as possible
    
  • Around 3-4 bays for 3.5" HDDs (one for parity)
    
  • m.2 slot for caching (not necessary though, it could also be an SSD)
    

I am replacing an old Synology DS120j, so I am sure anything above that will be way faster.

The mahine will be storing large 4k video files but will not be doing any Plex transcoding at all. It is mainly a share for all other LAN devices to share files

I am not interested in the following:

  • Any form of transcoding
    
  • Any form of VM
    
  • Any form of Docker (or other) containers
    
  • No ARM, must be x86
    

Trying to find a cost effective solution (aren’t we all), but if the hardware satisfies the requirements above, then it’s ok if it costs a bit more.

Your suggestions please?

Sounds like a 4 or 8 bay U-NAS would be a good fit.