Best PSU buying articles/resources?

Both Desktops and Servers

Seeking advice for your best "buying guides" concerning power supply units.

I haven't shopped for one in years because haven't needed to, things like normal PSU calculators seem to indicate "X is enough watts" when other sources suggest overbuying by at least 20% (so the PSU never loads more than 80% for efficiency/durability) or more for future capacity. I'm wondering if the calculation part is different for a desktop (which will tend to be in one of three states - idle, cpu maxed/like transcoding, or cpu+gpu maxed/heavy gaming) as opposed to a server (with loads all over the place covering lets say 1 to 16 hard drives, and also that I think the hard drives are powered off 5v rails not 12v like cpu/gpu?) and what are the most important factors that go into choosing a power supply somewhere between a range of "adequate" and "excellent". (adequate meaning for instance - not overrepresenting real wattage, full protection circuitry, and similar - nothing that will kill hardware if it dies, but something maybe that is the minimum cost to get by for now if money is tight)

There's lots of individual PSU review sites - thats not what i'm seeking. Looking for the general education first - including whats new information/knowledge now. (like seeing Haswells need special consideration/and assumedly later models including the new Ryzens... or that modified sinewave UPS's dont work with Active power correction, though I cant find any answer on passive power correction)
 

Patrick

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The server side is a bit easier. 99% of the server PSUs are basically whatever comes in the chassis.

There is very little market for this content otherwise we would have it on STH.
 

T_Minus

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-Desktop-
EVGA G2
EVGA G3
Seasonic Gold / Platinum and most Bronze

-Server-

Like @Patrick says whatever comes in it, you may be able to upgrade/downgrade in terms of power output and efficiency but usually cost does not justify that in the long run... the very common reason people here upgrade or swap server power supplies is for the quieter model units. SuperMicro brand has "SQ" model and they are most often found for 2-3x the cost of the same power output non-SQ model. I've also replaced some 1200W server power supplies with 520w because I don't need that insane power for powering ~100W of SSD but if I didn't have the replacements I would have just ran it :)

My other chassis that take unique power supplies or another company like Intel where DIY systems are much less common I'm running what they came with and most often they're very low sound, and even some are platinum level efficiency which is nice.



If I want to know something SPECIFIC about a power supply ie: internal components then I too turn to Johnny Guru.
I haven't compared/shopped in a couple years now but if you read their forums they will mention the things to look for 'in' a power supply that makes them last long, etc...

One main thing when looking to DIY with a desktop PSU in a server is to make sure you have the 4-Pin and 8-Pin motherboard connections available... some PSU will make you buy the cable additionally while others may not be provisioned for what you need and you'll need to split a molex power cable.
 
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The server side is a bit easier. 99% of the server PSUs are basically whatever comes in the chassis.

There is very little market for this content otherwise we would have it on STH.
Yes on the high end when it's all rackmount gear everything seems standardized around failover reliability and such. Everything i'm building will be shoestring for a number of years yet right down to my SAS Expander chassis, and since i'm going to be setting up multiple computers instead of just a one time buy (building PC's for everyone in a group actually/i'm turning into the defacto local expert for now) saving $10-20 per PC starts to add up to affording more TB of storage again. :)

Meanwhile two votes for johnnyguru, and i'll give them a lookout, are there any other really great websites, "learn it all guides", and similar to bring me up to speed? Things like power factor correction didn't even exist then, nobody worried about your PSU not working with your UPS, and nobody had to buy Haswell specific PSU's. Those three changes made me worried and wondering what ELSE might be different by now because clearly i've been out of keeping up on research too long. Mostly just decided it's probably time I learn everything "once and for all" from all angles and become an expert on it.
 

T_Minus

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johnnyguru will bring it down to the component level in the PSU they're that specific. You likely won't find another source picking up where johnnyguru left off because they'll likely have covered it, and if not their forums probably did. If you have a PSU thought or want to compare check out their reviews and then check out their forums for even more specific. Most any current power supply will be haswell compliant even my very old systems worked fine fwiw.
 

Bill1950

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I always thought the best advice is to get a power supply that is a significant overkill for it's use. The kind of hardware we're discussing on these forums are worth too much to jeopardize on an under-powered ps. Better to get too much than not enough. If it appears that 500 watts are requried, then get a good quality 850 power supply and don't worry. Adding 4 - 6 more hard drives? Add 100 watts of ps. Adding a high-end video card? Look at the manufacturer's specs for peak power use and add at least 150% more ps. Better to be safe than damage an expensive system.