The "gang of arms" lives on though in Ampere and graviton2 and the like.
Not knowing what the workload is, it's hard to beat consumer gpus for performance and price.
Just asking out of curiosity: Why not a Ryzen 16-Core CPU + 128GB RAM and then VMs / containers everywhere? To me that seems much less hassle than having to pet four machines, as I am way too lazy to write automation stuff for myself. Also such a setup setup needs less space and probably less power.
It will be harder to simulate failure there to see how the system behaves in such a case. You could just remove ethernet cable or remove a power cable, and see how it reacts.
How do you tell which of these available boxes has Intel AMT (or its AMD equivalent) fully enabled?
No listing reports this, and sellers seem to not be able to answer the question either.
How did you figure that out? Or are you managing without remote management? If so, how?
I use 4 Lenovo M910x's as a kubernetes cluster and home lab. Have them all connected with a netgear switch. The whole setup costs about the same as a single new quality work station. Each has: i7 8700 (6c - 12t) 32gb memory 1TB SSDs <1L case they're practically silent. easy to find parts, they even use lenovo laptop chargers. if one dies, I can easily purchase + replace in a few days.
You can even go cheaper if you don't need the absolute fastest cpus. Some of these older tiny computers can be purchased for around 100 bucks if you look for them. It has worked like a charm for me. Not sure how much horsepower you really need, but this is a cheap way to build a home cluster. I think they hover around using 40w most the time, so power isn't really too big of a cost either.