Seasonic PRIME 850W Platinum Power Supply Review @ [H]

FrgMstr

Just Plain Mean
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Seasonic PRIME 850W Platinum Power Supply Review - As is usual, Seasonic talks softly and carries a big stick. The biggest stick lately has been its Prime series power supplies. Today's Prime comes to us touting excellent efficiency, a fully modular design, tight output voltage, and a quiet noise profile supplied by a fluid dynamic bearing fan. Does Seasonic continue its current reign?
 
That is one hell of a great value. Thanks for the review, [H]... I'll probably replace my aging X750 with one of these when I overhaul my system next Feb-Mar.
 
Seasonic will be adding a Gold version to their Prime line up correct? The difference between Titanium and Gold level units is not significant enough to me to warrant the cost (again for me, if you have a high end rig by all means get the best) so I'd prefer so save some $$ and get a really good unit instead of a fantastic unit.
 
Seasonic pretty much always kills it. That's why they continue to get my cash, and why I often use their PSUs in builds for other people.
 
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This looks good. I was thinking about a Seasonic 750w titanium prime. I think I will only buy Seasonic psu's from now on. Even though the psu I have now has never let me down. I want fully modular also.
 
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I don't see an issue with the 'noise' parts of the reviews here. Anyone who is running a 850 watt P/S will have plenty of noise from the cooling of the system that the noise from the P/S is moot unless it has some crazy whine. In which will definitely show up in the review.

If noise IS that big of an issue then you would be looking for a 'fanless' type of P/S anyway. Or you would just install your own hand picked custom fan and install it yourself.

Anyways, nice review as always & don't change a thing. Power supply reviews are my absolute favorite thing about the [H]. I just wish I could have smellivision so I could SMELL the new hardware in the pics.:geek:
 
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Here is my noise comparison review for those who need to know: <ear placed next to Seasonic power supply> Yeah, it's quiet. <check mark placed in box> I hereby declare this power supply approved for the Unobtanium Seal of Quietness.

Shameless "fan" (nyuk-nyuk) of Seasonic since the SS-400HT.
 
Got me the Prime750W Platinum for R5-1600X.

Very good first impression, from A-Z. Can't say more cause it only runs the 2nd day now. Hopefully for the next 7 years to come or so.

I used to buy Corsair AX-i for High End but this has changed now. Seasonic is my new King for PSU demands.
 
If I was doing a build now, this would be my power-supply. My Seasonic X-850 has been running perfectly for nearly 4 years now.
 
Kyle, when testing these power supplies, do you hook them up straight to the outlet?
Do you ever test them when connected to an UPS?

I'm curious how some of these power supplies function with the simulated sine wave (vs. true sine wave) output from some UPS.
I've heard some power supplies do not function well with a simulated sine wave UPS and would love it if you included this check in your power supply tests.
 
Kyle, when testing these power supplies, do you hook them up straight to the outlet?
Do you ever test them when connected to an UPS?

I'm curious how some of these power supplies function with the simulated sine wave (vs. true sine wave) output from some UPS.
I've heard some power supplies do not function well with a simulated sine wave UPS and would love it if you included this check in your power supply tests.
https://www.hardocp.com/article/2007/02/25/hard_look_at_power_supplies/
 
[H]> "The topology is again a full bridge resonant LLC primary and a secondary where we have synchronous rectification with DC-DC VRMs for the minor rails."

What exactly were you smoking when you jumbled all those techno-words together?
Cause it looks to me like rather ordinary active PFC boost, bulk capacitance, half bridge,
resonant LLC, isolated step-down, synchronous rectification, with magamps for minor rails...

The extra "LC" in "LLC" (and I do see them in the picture) is only needed for a frequency modulated half-bridge.
Full bridge would typically run at fixed frequency, use phase shift for PWM control, and omit those other parts.
Doesn't have to omit them, but an advantage of full bridge is that it allows to omit them. Why you would spend
for two extra transistors and an extra high side driver, if you aren't getting rid of the excess cap and coil?

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And lets be clear to our readers, this "LLC" has entirely different meaning than LLC seen in BIOS.

"LLC" in the main supply means "Inductor Inductor Capacitor", a resonant supply topology.
"LLC" in the BIOS means "Load Line Calibration", for point of load regulation at the CPU.

I was confused as hell when I first seen that in BIOS, lookin all over the motherboard for
a cool running resonant power converter that didn't exist. Nope, all I found was the usual
multi-phase hard switching garbage with giant heatsinks to deal with the waste...

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As for some not working well with non-sines. That could be a flaw in the PFC design.
The current waveform needs to resemble the voltage waveform to fake like a resistor.
But I can definately imagine some dummy plagiarizing reference circuits from a book
would never even ask the question.

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How well does it run on 220 might also be a relevant review point to some.
Did I really need that clothes dryer? What about the stove?
 
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