Seasonic Focus Plus Gold 850 PSU Review

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Final Analysis

The following video footage shows the unboxing and internals of SSR-850FX.

Seasonic offers high performance to the masses with its new Focus line, and it scores big points with aggressive pricing. Right now, you'll find lower-efficiency competitors with inferior build quality and fewer features at the same price points as Seasonic's Focus Plus Gold models. That makes picking these PSUs a no-brainer.

The SSR-850FX is the Focus Plus Gold's flagship, featuring excellent load regulation, great ripple suppression, a long hold-up time, quiet operation under low loads, and a good transient response at +12V. Its most notable weaknesses are the minor rails' average transient response and the 5VSB rail's middling efficiency. It would be also nice if Seasonic used a regulator IC with over-current protection for the -12V rail. Otherwise, if you heavily overload that rail, the PSU will break down. Fortunately, most components don't use -12V any more. Still, in an advanced platform like the one Seasonic built, we want to see every possible protection feature enabled.

In addition to its relatively affordable price tag, the SSR-850FX boasts particularly compact dimensions for an 850W PSU. Moreover, its six PCIe and two EPS connectors ensure compatibility with high-end PCs. It used to be that enthusiasts didn't have to care how many EPS connectors their PSUs included. But today's high-end CPUs often require more power than one EPS connector can deliver, leading to major compatibility issues.

Seasonic's semi-passive mode should please builders specifically looking for quiet operation. Of course, when you push this PSU hard enough in a warm environment, that 120mm fan will make its presence felt. That shouldn't happen often; after all, 850W of output is a lot, even for a high-end system. If you don't want the fan to spin down under light loads, you do have the option of turning the SSR-850FX's semi-passive mode off. We always appreciate when manufacturers give you this choice, rather than forcing one configuration or another.

Simply put, the SSR-850FX is a great bargain at its current price. At the time of writing, EVGA's notably inferior 850 B3 costs just as much, yet offers much lower performance, achieves worse efficiency, exhibits questionable build quality, and is backed by half of the Focus PSU's warranty coverage. We don't know how, but Seasonic is keeping the price low on these models, creating huge problems for the competition. That's good for educated enthusiasts, though. Other manufacturers will have to drop their prices in order to battle Seasonic's Focus family.


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Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.

  • JohnnyLucky
    Nice review. I'll add it to the psu recommendation list I maintain.

    Last week newegg had the 650 watt model on sale for $74.99. There was a $20.00 mail-in rebate which brought the price down to $54.99. On top of that there was a free $30.00 gift certificate for a fresh food vendor online which my wife wasted no time in using. That brought the final price down to $24.99. Best deal I've taken advantage of this year.
    Reply
  • JohnUSA
    I just found this model selling for just $74 at SuperBiiz-dot-com, which I think is a great deal.
    Reply
  • buzznut47
    This was rated highly by JonnyGuru, and based on that I made a purchase 2 or 3 months ago. I have been mostly happy with its performance. I am running an FX 8320 @3.8 Ghz, 2 R9 280X, custom loop with 8 fans, and a couple of drives.

    Initially I was really impressed that there was so much power in such a small package. Until I saw the cables, and the ridiculous capacitors. I know this brings a fantastic level of ripple, but I don't like it at all.
    I gotta say, I really don't like this trend with higher end power supplies. As a modder, my cables are visible. And these cables would be satisfactory, if the capacitors were located ON THE PSU SIDE!! But they are located on the component side where they can be seen in all their glorious ugliness. It is not recommended to change the polarity..
    I will be checking the units I buy more carefully moving forward. I would much rather have a longer power supply unit that has the caps inside.

    Bottom line though, it is a gold 850W unit at an affordable price and a 10 year warranty. For efficient cards like the RX570/580 and GTX 1060, there are enough cables for 6 video cards. Pretty good for mining, but as for a visible gaming rig I have to say 4 out of 5 stars for functionality. Just put the caps at the other end of the cable, ya big dummy.
    Reply
  • berezini
    Still haven't changed my mind on getting one after killing my new motherboard and couple other components. Just would never recommend seasonic ever again.
    Reply
  • ZRace
    Great review, looks like this will be my next PSU unless something better releases by the time I need a replacement. Definitely gonna recommend this to others!
    Reply
  • JohnnyLucky
    ARIS - Are you still here?

    The PCIe cables are a little different than what I am used to. The 850 model and my 650 watt version have PCIe cables with two connectors instead of just one at their device end. Does that mean one PCIe cable can be used for both connections on a graphics card? On the other hand do I still have to use two PCIe cables and let one connector on each cable just hang there?

    Anybody else know?
    Reply
  • Leaps-from-Shadows
    20427267 said:
    Still haven't changed my mind on getting one after killing my new motherboard and couple other components. Just would never recommend seasonic ever again.
    Even the best manufacturers produce the occasional lemon. It's too bad you're one-and-done -- you're really missing out on quite possibly the best power supplies out there.

    It's okay though ... they will survive without your money.
    Reply
  • Leaps-from-Shadows
    20430290 said:
    ARIS - Are you still here?

    The PCIe cables are a little different than what I am used to. The 850 model and my 650 watt version have PCIe cables with two connectors instead of just one at their device end. Does that mean one PCIe cable can be used for both connections on a graphics card? On the other hand do I still have to use two PCIe cables and let one connector on each cable just hang there?

    Anybody else know?
    You can certainly use the two connectors from a single cable. However, a video from JayzTwoCents showed it was better to use two separate cables.
    Reply
  • JohnnyLucky
    Leaps - Thanks for the info.

    I went back and read the review. In the specs it shows 3 PCI-e cables and 6 connectors. It also indicates the 3 cables could be used with 3 video cards, each requiring 2 connectors.

    I'll take a look at the video. I've watched some of his other clips.

    Don't know how I missed this development.

    Reply
  • Leaps-from-Shadows
    20430533 said:
    Leaps - Thanks for the info.

    I went back and read the review. In the specs it shows 3 PCI-e cables and 6 connectors. It also indicates the 3 cables could be used with 3 video cards, each requiring 2 connectors.

    I'll take a look at the video. I've watched some of his other clips.

    Don't know how I missed this development.
    Here it is, in case you couldn't find it...
    Reply