[echlebek]

I don't think that's true either. You can get 8-core desktop Ryzen parts that have a TDP of 65 watts. I have a passively cooled 8-core Ryzen system that uses a 240 watt power supply.

Also: by the time you've wired up 8 raspis you end up using quite a bit of power just to connect them all together with a switch.

Raspberry Pi 4s need a maximum of 15 watts each. So 120 watts just for the computers. Even if you discount the power consumption of the switch, my 240 watt Ryzen computer is still going to beat that joule-for-joule.

Edit: one more thing, that 240 watt system also powers a 75 watt GPU, so it's definitely more wattage than really required for the CPU alone.

[willis936]

You're calculating the raspi 4 power consumption based off of recommended USB power supply current rating. The actual expected load power consumption without peripherals is 1/5 to 1/3 of that (3-5 W rather than 15 W).

https://www.raspberrypi.org/documentation/hardware/raspberry...

https://www.pidramble.com/wiki/benchmarks/power-consumption

https://raspi.tv/2019/how-much-power-does-the-pi4b-use-power...