
I mean why 20W?
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I mean why 20W?
NAS. 1 drive = maybe 8 watts. Motherboard itself = 12w.
So with 20W DC draw, a PSU at 85% vs 90% efficiency would be a difference of 1.29W from the wall. Probably not worth spending more money on that 5% difference, but for the same price might as well get the best you can.
Why does it matter?
Power ain't cheap, especially in a NAS configuration where it'll presumably be running 24/7.
Power is cheaaaaaap https://www.globalpetrolprices.com/electricity_prices/ unless you pull like 100 W. Having said that, I'd go for ARM or x86 SoC that pull like 15 W through a wall wart as opposed to a full ATX PSU.
1.3 W is around 1 kWh per month. I checked on local electric company's website, that's around 0.2 USD per year here. Prices may be diffferent wildly worldwide, but we are definitely speaking about a less than 10 USD difference yearly.
A NAS with only 1 drive? Is that a thing?
It's a 3-2-1 backup, one drive is 16tb and the other is a backup that turns on once a week. If one drive fails they're under warranty. Files are also uploaded to the cloud.