Raspberry Pi Zero 2 W

[mrburnette]

A quick google search showed me this article that claims the pi zero 2 is the most power efficient raspberry pi so far: https://hackaday.com/2021/11/01/the-pi- ... icient-pi/

and if you want to make it even more power efficient, here's how to disable some cores on it:
https://www.jeffgeerling.com/blog/2021/ ... ption-half

Respectfully... Power efficiency is a term that can be tossed around to compare any two electronic devices: arc welders, for example. It alone does not mean the product is suited for battery operation over an extended period.

Looking first at the memory bandwidth scores, the 4B is way out ahead, and the old Pi Zero is bringing up the rear, but the 3B+ and the Zero 2 are basically neck-in-neck. What’s interesting, however, is the power used in the memory test. The Zero 2 W scores significantly better than the 3B+ and the 4B. It’s simply more efficient, although if you divide through to get memory bandwidth per watt of power, the old Pi Zero stands out.

... and why oh why disable "some" cores. This mucks with any multi-threaded work load.

One must start with a clear understanding of the design goals and electrical power provisioning: AC, battery only (Alkaline, LiON), supplemental power (solar, thermal pile) and then deal with the computational aspect - numbers of sensors, processor algorithmic processing, data transmission and storage. Every "power" component has a "time" component; thus, for any given computational system, the longer a process takes, the more power is utilized. Shutting off cores could increase the power consumption but, for single-threaded workloads it is likely that selecting a multi-cord processor was a poor engineering decision.

[ag123]

Another thing more interesting is that this is Raspberry's own chip, just like the pico.
Due to chip shortage etc, it is rather interesting that Farnell (Element14.com) which used to keep quite some stocks of RPi boards (they probably manufacture it themselves), is on back order basis when I last checked recently. There are other vendors that stock them though.
For a while, I've been thinking where the shortage really is, I'd think it isn't really those desktop processors from Intel / AMD etc, servers may be an exception.

But that what is really short may well be microcontrollers like stm32, prices apparently has gone up as well. The last time when I ordered my pico boards (from Farnell Element14), it is also on back order basis. So I'd guess the lines are after all really busy. 'fabless' chip makers may well be caught in the same queue as microcontrollers and possibly the Arm Cortex A chips as well.

Pi Zero 2, should probably be considered a different product with a same *form factor*.
Raspberry Pi these days is becoming a *Form factor* - just like the PC days, especially the Model B.

So much so that, 3rd party are selling elaborate *cpu coolers* for them
https://thepihut.com/products/ice-tower ... cpu-cooler

[mrburnette]

Another thing more interesting is that this is Raspberry's own chip, just like the pico.
...

https://www.raspberrypi.com/news/new-ra ... ero-2-w-2/

Priced at $15, Raspberry Pi Zero 2 W uses the same Broadcom BCM2710A1 SoC die as the launch version of Raspberry Pi 3, with Arm cores slightly down-clocked to 1GHz, bundled into a single space-saving package alongside 512MB of LPDDR2 SDRAM. The exact performance uplift over Zero varies across workloads, but for multi-threaded sysbench it is almost exactly five times faster.

[ag123]

Another thing more interesting is that this is Raspberry's own chip, just like the pico.
...

https://www.raspberrypi.com/news/new-ra ... ero-2-w-2/

Priced at $15, Raspberry Pi Zero 2 W uses the same Broadcom BCM2710A1 SoC die as the launch version of Raspberry Pi 3, with Arm cores slightly down-clocked to 1GHz, bundled into a single space-saving package alongside 512MB of LPDDR2 SDRAM. The exact performance uplift over Zero varies across workloads, but for multi-threaded sysbench it is almost exactly five times faster.

Interestingly, it labels different here:
https://www.raspberrypi.com/products/ra ... -zero-2-w/

oh it is still different, know where? the dram is inside the soc capsule

[racemaniac]

except for one thing: the 5V@2.5A power requirements.

I really feel like i'm having a conversation with a brick wall here. How many more sources do i have to cite that measure the actual peak power, which never exceeds 500mA.

Yes, someone somewhere wrote a 2.5A power supply is recommended. That does not mean that that's the actual peak power consumption in the usecase you guys are thinking of. People have measured it, i've linked articles & videos talking about it. It will never ever come close to drawing 2.5A all by itself.

[mrburnette]

...
I really feel like i'm having a conversation with a brick wall here. How many more sources do i have to cite that measure the actual peak power, which never exceeds 500mA.
...

Yes. We know but other than form-factor, this thing is not a "Zero" and calling it a Zero is blatant misrepresentation of the cpu utilized.
Raspberry Pi Foundation could have done better by keeping "3B" in the model naming ... maybe 3LP for low-profile or low-power or littl'pi.

[ag123]

oh at least they did a feat to cramp a piece of dram on top of the cpu soc. Not very wise, but i'd guess they 'ran out of space', is there anything at the bottom of the board?

[racemaniac]

...
I really feel like i'm having a conversation with a brick wall here. How many more sources do i have to cite that measure the actual peak power, which never exceeds 500mA.
...

Yes. We know but other than form-factor, this thing is not a "Zero" and calling it a Zero is blatant misrepresentation of the cpu utilized.
Raspberry Pi Foundation could have done better by keeping "3B" in the model naming ... maybe 3LP for low-profile or low-power or littl'pi.

but it uses far less power than a 3B would use O_o (about half i think?)

Why are you guys so stuck on this not being a zero? It's 5x faster than the old zero, uses about double the power of the old zero. If power consumption is all you chase, stick to the older one, but this one seems like a nice iteration, giving you a second small formfactor choice with greatly improved performance, but indeed consumes more power. it's somewhere in between the old zero and a raspberry pi 3 regarding power consumption. So dismissing it as a small formfactor raspberry pi 3 seems pretty silly too >_<.

[ag123]

'zero' is probably a 'unnecessary' 'form factor' constraint, though Raspberry seemed to sell on the 'form factor'.
A slightly larger board with different layout would likely fit the dram on board in the usual way, that'd also offer an easier way to change the dram capacity as like the Pi4. I'd guess Rpi is kind of trying to make a 'distinctive' product

to play the 'form factor' game, one'd need to pack enough peripherals and connections on board as like the Model B+ with usb and all, the multitude of peripherals + a huge oversized giant cpu cooler would make way for the 'form factor industry' the notion is to have the whole industry make cases, cpu cooling fans and even power suppllies for it as does that plain old ATX 'form factor', i.e. it needs to deserve to sit on the desktop. intel played that game with its proprietary NUC form factor. Maybe the next RPi should add a SATA controller so that you'd connect your terabyte SSD to it

[mrburnette]

'..
Maybe the next RPi should add a SATA controller so that you'd connect your terabyte SSD to it

External controller, but...
https://thepihut.com/blogs/raspberry-pi ... spberry-pi