What pi has the best performance/watt?

[bomblord]

I have an idea for a project in mind (that may or may not happen this is purely theoretical and I'm not sure I want to dump money into it yet) whose usage hinges getting the maximum possible performance out of a limited amount of juice. The project would be an emulation machine running old Gameboy/Color and or equivalent games off a battery and attempting to push the battery life as far as possible. Depending on how well this works I may attempt to exclusively charge the battery off a moderate sized solar panel.

Assuming underclocking/undervolting is not off the table which of the available raspberry Pi's can get the best performance out of the least amount of consumed energy?

[bjtheone]

I would think you would have to define the required "floor" performance your project requires.

[hippy]

The answer would always seem to be that a Pi Zero offers best performance per watt unless you need more performance than a Pi Zero can deliver.

A Pi Zero flat out will draw 350mA (1.75W). A Pi 4B idling draws 600mA (3W).

[HermannSW]

The question is underspecified.

What is "performance"?
Is it idle run, heavy run or 100% for the CPU(s)?

What should be computed in order to compare?
Without anything meaningful to compute, Pi2B would be best with only 400mA for 400% CPU:
https://www.jeffgeerling.com/blog/2018/ ... comparison

Typically one should ask "what pi is the pest for benchmark XYZ/watt".

[gordon77]

This site gives some comparisons between models of Pi on power and performance
https://medium.com/@ghalfacree/benchmar ... e5afbcd54b

[trejan]

If you're only looking to run GB/GBC games then a Pi Zero would do it and it has the lowest power consumption. Look at the RetroFlag GPi case.

[bomblord]

The question is underspecified.

What is "performance"?
Is it idle run, heavy run or 100% for the CPU(s)?

What should be computed in order to compare?
Without anything meaningful to compute, Pi2B would be best with only 400mA for 400% CPU:
https://www.jeffgeerling.com/blog/2018/ ... comparison

Typically one should ask "what pi is the pest for benchmark XYZ/watt".

Game boy color emulation. Want to use the least amount of power with undervolt/underclock on the table for GBC emulation.

[wildfire]

And what screen / controllers would you be using?

The aforementioned Retroflag case gives me around 5 hours usage from 3 AA batteries with a Zero W, YMMV.