Yeah, I think the correct sticker on a PSU would be something like 80 Plus Ruby?! Everything else comes with 80+% efficiency at 20% rated load. Which is 200W for a 1000W PSU. And there’s no guarantee on what happens below that, so it might very well be utter garbage at a home server power draw of 20-30W.
You never know without looking up the datasheets. Though, back when I built my home server/NAS, I failed to find a good one. I got a PicoPSU and a 12V power brick instead. Not sure if that’s still a thing. But I remember it was a lot of work to find proper and efficient components. And it doesn’t make any sense to put in all the effort (and money) and then burn all the saved energy, and then some more, in an average PSU.
Some MiniPCs, NUCs and even computers also come with fairly efficient power supplies.





Speaking from my own experience… Lots of people try to cobble together information and try to learn something quick. To varying degrees of success… But it’s a bit of a hit and miss sometimes. And you don’t necessarily learn it the proper way or the right way around if you go by the random order your questions arise.
I think one of the most efficient ways (and least time-consuming in the long run) is still good old books. They’re mostly written by clever people. And they come with the information curated. And laid out in the correct order, so you’ll get the basics first and then the stuff building on top of that. So you don’t need to waste a lot of time jumping back and forth and get entangled because you don’t really know you’re missing some basics while learning some advanced concept.
It’s not easy either. I mean first of all you gotta find some book that matches your learning style. And then I regularly struggle with the first few chapters because I kind of already know 70% of the stuff, yet not all of it. So it’s tricky to hit some balance between brushing over things, and not missing important information… But it gets better after that.
But I think more often than not, it’s the proper way. And since it’s curated and all, it’ll save time in the long run.
(I can’t really compare it to the AI approach. I’ve used AI to look up documentation for me. But never used it to learn any more complicated concepts. So I don’t have any first-hand experience with that.)