[rewmie]

> I don't think that estimate takes into account the power savings (...)

I don't think this is relevant. RPis cost is a critical factor in it's usefulness as a disposable toy computing platform, not web servers that need to run 24/7.

Moreover, that cost is further worsened by the need to buy a custom power supply.

[LeafItAlone]

I have two RPi 4s that run 24/7 that I will likely replace with a 5.

> Moreover, that cost is further worsened by the need to buy a custom power supply.

But you don’t need to?

[rewmie]

>

From RPi5's FAQ:

> Raspberry Pi 5 is a higher-performance computer than Raspberry Pi 4, and you may have problems using an under-powered supply. We recommend a high-quality 5V 5A USB-C power supply, such as the new Raspberry Pi 27W USB-C Power Supply.

As mentioned in a previous HN discussion, not only was RPi5 designed to require a nonstandard power supply, the official "high-quality" power supply for the RPi4 is also considerably underpowered at 15W at 5.1V-3A[1] while RPi5 stands at 27W at 5V-5A.

[1] https://www.raspberrypi.com/products/type-c-power-supply/

[LeafItAlone]

Their FAQ is definitely unclear, but, as mentioned in a previous HN discussion, a 5V/3A is going to work fine for most workloads. They limit downstream USB current to 600mA. If you need the full 1.2A limit, you can buy their power supply, another (not common) one, or a powered USB hub.

5V/5A will also give you 5W extra power on the device for their high performance mode.

But again, it’s not necessary and most uses of a Pi will do fine with 5V/3A.

[rewmie]

> Their FAQ is definitely unclear, but, as mentioned in a previous HN discussion, a 5V/3A is going to work fine for most workloads.

I don't think so. Historically, Raspberry pi board always had non-standard power requirements and always required rpi's official power supply to work reliably. My RPi4 board forced me to buy the official power supply to work without weird problems and I did nothing but vanilla stuff with it.

RPi5 worsens this problem by requiring a power supply that draws 5A.

[sgerenser]

Depends on what you’re doing with it. For many things it will run fine off of a 3A 5V supply, which almost any usb-c adapter will do. But as soon as you start hanging any USB devices off of it, IIRC you need a 5A/5V supply which is unusual outside of the RPi-specific one.

[LeafItAlone]

Yes, and it depends on the devices. 5V/3A will limit USB power to 600mA. Could also use a powered USB hub.