| The use case is greenwashing and separating people from their money because everyone thinks Pis are just the bee's knees. The Pentium G6400 outperforms a Pi4 4-5x, and has a 54W TDP (onboard GPU so at least part of that is for the GPU, so CPU-only workloads will be less.) The Ryzen 5600x is 65W and is twice as fast (at least) as the G6400...so in theory a 5600x is twice as energy efficient as a Pi4 if fully loaded. Sure this doesn't account for system fans and the motherboard, but they don't use that much compared to the CPU. The whole point of virtualization is that most systems are idle a lot of the time. At datacenter scale virtualization, you can dramatically over-provision and shut down/sleep unnecessary nodes, firing them up when you need to. You can get near 100% utilization on your hardware, making the very most of every watt that doesn't go to actually computing. Here they're going to have a zillion Pi4's, most of them sitting idle, but still using a couple watts. They're not even bothering to use any sort of shared power to improve PSU efficiency. They're not even bothering to use Pi4 compute modules. Now, the interesting bit is that now there's the Pi Zero Wireless 2. It has nearly the compute power of the 3B+, but the highest energy efficiency per watt of any Pi board so far... |
That's more energy efficient, sure. But it sets a lower boundary on the power draw much higher than a normal Pi. A Pi plus a single external HDD draws 12W at the socket, according to my measurements. A PC CPU draws 4-5x that, just by itself. The other components on the motherboard need power too, even if you use integrated graphics or no graphics at all.
A PC only becomes more power-efficient if your load can't fit in three or more Pis. For plenty of uses, more than two Pis are an overkill.