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by vladvasiliu 1966 days ago
Regarding power usage, I'm not very familiar with how those drives compare [0]. To be honest, power consumption was of interest for the build I was talking about because I wanted it to be fanless (I actually ended up adding a very silent fan, just for peace of mind). For my NAS needs, I'm building in a recycled server, so power usage isn't as much of a concern.

However, I did look for 2.5" drives (the server comes with a 2.5" backplane) and there don't seem to be many "consumer" drives in this format that are both high capacity (>2 TB) and non SMR (I'll be running ZFS). I'm also not looking to spend very much, so SSDs are out.

[0] Seagate specs for 2.5" Barracuda: https://www.seagate.com/www-content/datasheets/pdfs/barracud...

The startup current is 1.2 A under 5V. So if you're running four of them, you'll need 24 W just for the drives. Not sure if the "cheap" enclosures are able to stagger drive startup.

My Gigabyte motherboard cannot, so it would require a PSU large enough to drive both the board (CPU + RAM + etc) and the drives for a little while. So with four drives, you'd be looking at 50 W to be sure it fits.

1 comments

50W is way more than I am willing to operate. I want it to be extremely low powered. I think that a 2.5 inch SSD might be a better fit for me then, maybe M.2 if there's a adapter for the PI.

SSD and low cost is still possible, but one has to make compromises in terms of storage size. A 1 TB network drive would be enough for my use case, be it 4 x 256 SSD's or one big.

Peak power is significantly different from operational power on many of these setups. The intel setups, frequently idle at a 1/10th or less the rated power. The rpi4 OTOH, isn't nearly as dynamic, particularly if your running 64-bit debian. Its still just a few W, but its not going to drop down into the mW range when its idle because debian/etc doesn't have particularly good power mgmt on that board.

So in the end the rated W can be quite misleading, particularly for home use where the NAS will tend to sit idle a large part of the day.

Okay, but what I really wanted to say is that I want a very small and low powered NAS without a big PSU. The PI is powered over USB, that's fine for me.