What's kind of messed up, at least for tiny companies like mine, is that renting an ugly PC-based dedicated server from a company like OVH is currently cheaper than paying for the equivalent computing power (edit: and outgoing data transfer) from a hyperscale cloud provider like AWS, even though the hyperscalers are probably using both space and power more efficiently than the likes of OVH. My cofounder will definitely not get on board with paying more to get the same (or less) computing power, just for the knowledge that we're (probably) using less energy. I don't know what the answer is; maybe we need some kind of regulation to make sure that the externalities of running a mostly idle box are properly factored into what we pay?
> renting an ugly PC-based dedicated server from a company like OVH is currently cheaper than renting the equivalent computing power from a hyperscale cloud provider like AWS
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.
Sure, the CPU may enter a power-saving state, but presumably for each box, there's a minimum level of power consumption for things like the motherboard, BMC, RAM, and case fan(s). The reason why AWS bare-metal instances are absurdly expensive compared to OVH dedicated servers is that AWS packs more computing power into each box. So for each core and gigabyte of RAM, I would guess AWS is using less power (edit: especially when idle), because they don't have the overhead of lots of small boxes. Yet I can have one of those small boxes to myself for less than I'd have to pay for the equivalent computing power and bandwidth from AWS.
Interestingly, I believe that unused DIMM modules could be powered down if the hardware bothered to support that. Linux has to support memory hotplug anyway because it's long been in use on mainframe platforms, so the basic OS-level support is there already. Since it's not being addressed in any way by hardware makers, my guess is that RAM power use in idle states is low enough that it basically doesn't matter.
