Now here is the thing: I also often hear about (and partly experienced myself) this exact situation. However, the problem with all these low power small form factor x86 PC's (like the Odroid H4) is, that there is not much review material.

I, personally don't think they are worth the money. Many people drastically underestimate the "low power" capabilities of x64 server hardware (let's say Dell T30 or Fujitsu Workstations) and to be honest: Spending a huge amount of money to save a few watts won't pay off in the near future.

So, the questions are: How much money would you like to spend? How much "powerful" do you need? And last, but not least: Which other features are important (like ECC RAM, 2.5Gbe, NVMe, SATA Ports, Remote Management / IPMI)?

I would go for one of these:

- ASRock N100DC-ITX (Non-Server N100 board with 6W idle power consumption)

- Odroid H4 (Non-Server N100 up to N305 board with ~5W idle power consumption)

- Gigabyte MC12-LE0 (Server Ryzen ECC board with ~25W power consumption)

- A used device like ThinkCentre, HP Prodesk / Elitedesk, Fujitsu S740 (Non-Server, ~8W power consumption)

I'm actually partial to the ASUS before they even took over the NUC line from Intel.

However it looks like there are off-brands having comparable specs for about half the price of the new NUCs.

A second-hand ASUS may be the best deal.

There are also "thin clients" from places like Dell or HP that are small, low power, and fanless. These can be really cheap when removed from office buildings in quantity. If you can get by with as little as 4GB of memory and 16 or 32GB of on-board drive space, surplus units like this are cheap because they don't really do much office work on their own or run Windows 11 by design.

Drivers can be a problem, even in Windows. I had some Minix Windows 8 minis from our IT guys that I repurposed for scientific use. A single advanced Windows 10 app ran OK and did not overstress the little things, but at the beginning Windows Update did not recognize many of the uncommon mini hardware items. The only way to get all the hardware working was to point Windows 10 to the driver repositories in the original mounted Windows 8 recovery image.

They did what I set out to do, but when I tried to set one up as a mobile hotspot, that particular feature was not supported by the hardware.

That site also has reviews of various newer mini PCs if you still want to go that route.

- Lenovo ThinkCentre M910q Tiny | i7-7700T | 16GB RAM | 512GB M.2

For $150/ea. Comes with windows but ubuntu server was a quick & painless install on them (no driver issues).