I went in thinking that maybe there's something to learn for my grand total of 1 ThinkCentre M910q "homelab", but this author's setup is on another league, I'm sure closer (or surpassing) the needs of a small/medium company!
They never were terribly cheap, but there was a time when people who hadn't seen a single-board computer (that small) and didn't really keep abreast of the used market gobbled them up.
One advantage over the used market is that you can easily keep getting the exact same one over and over again.
Not really, no. Not if all you need is "a computer". They're more interesting if you want a cheap ARM computer, or a tiny computer, or a server that sips power. Although for that last one they're also kind of dubious. If you can somehow get away with running what you need off a phone, that's way better value.
You'd be delighted (or terrified) to know that I just added an old gaming computer in a 4U case to the cluster, so I can play with PCI/GPU passthrough.
The Dell is essentially the main machine that runs everything we actually use - the other hardware is either used as redundancy or for experiments (or both). I got the Pi from a work thing and this has been a fun use case. Not that I necessarily recommend it...
