That would be nice, but Synology doesn't offer that either, no?

The closest thing available now would probably be a Radxa ROCK 5 ITX+, a motherboard with a Rockchip SoC and two M.2 slots, into which you could put their six-port SATA cards. No idea what that whole setup will draw, though.

EDIT: I have to complain about the article you linked. It's certainly true that one should account for power consumption, not just purchase cost, but some crucial mistakes make the article more harmful on the whole.

The author cites 84 W power consumption for an i5-4690, and 10 W for a J4125 CPU, but those figures are the TDP. For all we know, those CPUs could idle at around the same wattage, and from my experience they likely do.

Having done some measuring myself, I'd say the largest source of power draw in an idle NAS will be the PSU, motherboard, and disks. With any remotely recent Intel CPU, it idles so efficiently as to be negligible in a PC.

> That would be nice, but Synology doesn't offer that either, no?

I have a Synology DS920+ 4-bay that averaged 20W total including 2 spinning drives with sleep disabled. I agonized about going with the closed product, and in many ways regret it. But at the time there was nothing I could find that came close, even without the drives. And that's before factoring my time administering the DIY option, or that it would be bigger and less ruggedized.

I went as far as finding the German low power motherboard forum spreadsheet and contemplating trying to source some of the years old SKUs there. You've gotta believe us when we say that before the n100s arrived, it was a wasteland for low power options.

In many ways it still is, although these n100 boards with many SATA are a sea change. Once you set out to define requirements, you pretty quickly get to every ZFS explainer saying that you are a fool to even attempt using less than 32 GB of ECC memory...