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Seasonic Focus Plus Gold 850 PSU Review

Load Regulation, Hold-Up Time & Inrush Current

To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units. 

Primary Rails And 5VSB Load Regulation

Load Regulation testing is detailed here.

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Hold-Up Time

Our hold-up time tests are described in detail here.

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The hold-up time we measure is pretty long, and the power-good signal is accurate. This is what we expect from a Seasonic PSU.

Inrush Current

For details on our inrush current testing, please click here.

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With 115V, the inrush current is low. However, the situation turns with 230V input.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the SSR-850FX's efficiency. The applied load equals (approximately) 10 to 110 percent of the PSU's maximum load in increments of 10 percentage points.

We conducted two additional tests. During the first, we stressed the two minor rails (5V and 3.3V) with a high load, while the load at +12V was only 0.1A. This test reveals whether a PSU is compatible with Intel's C6/C7 sleep states or not. In the second test, we determined the maximum load the +12V rail could handle with minimal load on the minor rails.

Test #12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan SpeedPSU NoiseTemps (In/Out)PF/AC Volts
15.222A1.996A1.987A0.985A84.99286.748%621 RPM11.6 dB(A)41.65°C0.973
12.137V5.010V3.327V5.078V97.97647.59°C115.27V
211.485A2.997A2.979A1.184A170.30190.194%565 RPM10.7 dB(A)38.83°C0.988
12.136V5.009V3.325V5.069V188.81647.93°C115.17V
318.076A3.497A3.490A1.384A255.48391.014%550 RPM10.4 dB(A)39.01°C0.990
12.136V5.008V3.323V5.059V280.70648.41°C115.15V
424.667A3.997A3.973A1.585A340.57591.022%550 RPM10.4 dB(A)39.57°C0.991
12.136V5.007V3.322V5.050V374.16949.23°C115.03V
530.861A4.998A4.968A1.786A425.08290.655%560 RPM10.5 dB(A)40.75°C0.990
12.137V5.006V3.321V5.041V468.90350.75°C114.91V
637.117A5.997A5.965A1.988A510.38490.095%880 RPM20.6 dB(A)41.79°C0.991
12.139V5.005V3.320V5.031V566.49752.22°C114.88V
743.348A6.997A6.961A2.192A595.27889.427%1333 RPM31.4 dB(A)42.33°C0.991
12.138V5.004V3.319V5.020V665.66052.93°C114.75V
849.587A7.998A7.962A2.395A680.21288.693%1984 RPM41.5 dB(A)42.93°C0.992
12.136V5.003V3.317V5.011V766.92553.79°C114.72V
956.248A8.499A8.474A2.398A765.24187.942%2310 RPM45.1 dB(A)44.02°C0.992
12.136V5.002V3.316V5.006V870.16655.12°C114.58V
1062.643A9.000A8.958A3.009A849.95687.009%2320 RPM45.2 dB(A)45.40°C0.993
12.136V5.002V3.315V4.987V976.85756.83°C114.43V
1169.683A9.000A8.962A3.012A935.52585.851%2320 RPM45.2 dB(A)47.19°C0.993
12.138V5.001V3.314V4.981V1089.71458.87°C114.39V
CL10.159A12.001A12.000A0.001A101.98585.242%560 RPM10.5 dB(A)43.42°C0.983
12.145V5.008V3.329V5.092V119.64253.02°C115.24V
CL270.008A1.002A1.001A1.001A863.06387.262%2320 RPM45.2 dB(A)45.75°C0.993
12.137V5.004V3.315V5.039V989.04556.15°C114.43V

On every rail except the 5VSB one (which is still within 3%), the load regulation we observe is extremely tight. Seasonic's new platform achieves excellent performance in this discipline, despite its budget orientation. The measured efficiency levels are pretty good as well, while the fan profile is relaxed. It's only when you push the PSU hard, under 80% of its maximum-rated-capacity load and high operating temperatures, that the fan spins at full speed.


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  • 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