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Comment by youngtaff | Hacker News Reader

Have you come across anyone producing a PoE board for the CM4 - just looking for a network port, USB and perhaps SD card (similar to a Ubquiti Cloud Key)?

(the Gumstix camera board is overkill for my needs)

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Waveshare has one. Haven't used it personally but it seems to suit your needs. Though at ~$50 you're probably better off just getting a Pi 4B + PoE hat.

https://www.waveshare.com/compute-module-4-poe-board.htm

Can POE provide enough power to turn SATA drives? I kind of figured for a NAS it probably makes sense to go with a regular power supply, especially since it’ll be mounted in an easy to access location for drive replacement.

802.3at specifies max 30W at the output port at 600mA so in theory you could shunt that to 5V and get about 5A after losses. Enough to spin up a 3.5" SATA.

But most consumer retail PoE switches are only .3af compliant which give 15W minus transmission losses.

802.3bt can provide higher power, easily enough to run a few HDDs but there are few switches on the market that offer 802.3bt. Almost nothing available for the residential/consumer space.

A regular Raspberry Pi with a cheap POE USB-C splitter from Aliexpress works very well.

https://a.aliexpress.com/_mMpvxGV

Why not use the regular Raspberry Pi 4 with the PoE module?

The CM4 is only useful in most cases if you want to use the PCIe bus for something else, or if you’re trying to embed it in another product.

The existing PoE module is noisy as hell, and due to it's design it's a PITA to fit a different fan

CM4 on a PoE baseboard offers far more cooling options

"Have you come across anyone producing a PoE board for the CM4 ..."

Wait, I thought the official CM4 breakout/dev board (the one with the PCIe slot on it) had PoE, right ?

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