Cost competitive as it may be, it doesn't mean that it hits the price point for a home lab, sadly. One of the (many) advantages of an open source stack is allowing people to do these kinds of experiments on their own; looking forward to getting our schematics out there too!
I know several people with 2x 240V 32A 3-phase in their garage, that's 20+ kW at any reasonable power factor. But a 15 kW cooler that would work in summer would annoy the hell out of any neighbours living closer than a mile.
It would be nice to have a known pricepoint from a cloud provider which once exceed you ask the question: "Should we buy a rack and COLO it?" Even if the answer is "no" it's still good to have that option.
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The thing is: Datacenter technology has moved on from 2011 (when I was getting into Datacenters), but only for the big companies. (Google, Facebook, Netflix); I think Oxide is bringing the benefits of a "hyperscale" deployment to "normal" (IE; single/double-digit rack) customers.
Some of those things such as much more efficient DC converters, so not every machine needs to do it's own AC/DC conversion.
That's not surprising, you're basically paying for scalability. An idle box doesn't even necessarily "waste" all that much energy if it's truly idle, since "deep" power-saving states are used pretty much everywhere these days.
Each stick of DDR4 is going to consume on the order of 1.2w (idle CPUs can theoretically go lower than this).
I’d rather shut a whole machine down than go to the effort of offlining individual DIMMs, since the consumption is so low and quite static.
They’re not reasonably equivalent. But I don’t doubt that Amazon is laughing to the bank still.