XFX XTR Series 850W PSU Review

Efficiency, Temperature And Noise

Efficiency

Our efficiency testing procedure is detailed here.

Using results from the previous page, we plotted a chart showing the XTR 850W's efficiency at low loads, and loads from 10 to 110 percent of its maximum-rated capacity.

Efficiency is quite high, easily keeping up with the Gold-rated 750W units under both light and normal loads. The only 850W PSU in our charts, the Corsair CS850M, stays clearly behind especially at light loads.

Efficiency At Low Loads

In the following tests, we measure the XTR 850W's efficiency at loads significantly lower than 10 percent of its maximum capacity (the lowest load the 80 PLUS standard measures). The loads we dialed were 20, 40, 60 and 80W. This is important for representing when a PC is idle, with power-saving features turned on.

Test #12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan Speed (RPM)Fan NoisePF/AC Volts
11.198A0.490A0.475A0.194A19.6270.20%00 dB(A)0.868
12.158V5.040V3.352V5.120V27.95115.1V
22.422A0.989A0.984A0.390A39.7280.44%00 dB(A)0.935
12.159V5.039V3.350V5.113V49.38115.1V
33.653A1.474A1.491A5.104A59.8384.51%80532.5 dB(A)0.957
12.159V5.039V3.348V5.104V70.80115.1V
44.869A1.983A1.970A0.780A79.7386.20%80532.5 dB(A)0.967
12.153V5.038V3.345V5.100V92.49115.1V

Even with 20W load, efficiency stays above 70%. As you can see from the fan speed column, the fan operates in passive mode only during the first two tests and its minimum speed is set at 805 RPM, which translates to 32.5 dB(A) output noise. If you are after a dead silent PSU, this one probably won't cut it.

5VSB Efficiency

The ATX specification states that 5VSB standby supply efficiency should be as high as possible, recommending 50 percent or higher efficiency with 100mA of load, 60 percent or higher with 250mA of load and 70 percent or higher with 1A or more of load.

We take four measurements: one each at 100, 250 and 1000mA, and one with the full load the 5VSB rail can handle. 

Test #5VSBDC/AC (Watts)EfficiencyPF/AC Volts
10.101A0.5276.47%0.135
5.123V0.68115.1V
20.251A1.2978.66%0.255
5.120V1.64115.1V
31.002A5.1180.60%0.409
5.104V6.34115.1V
43.002A15.1979.45%0.493
5.059V19.12115.1V

The 5VSB rail stands very well against other Gold-rated units in the 750W-850W range.

Power Consumption In Idle And Standby

In the table below, you'll find the power consumption and voltage values of all rails (except -12V) when the PSU is idle (powered on, but without any load on its rails), and the power consumption when the PSU is in standby mode (without any load, at 5VSB).

Mode12V5V3.3V5VSBWattsPF/AC Volts
Idle12.164V5.041V3.356V5.128V11.130.663
115.1V
Standby0.100.022
115.1V

Power consumption at standby is very low; it doesn't exceed 0.15W even with 230V input.

Fan RPM, Delta Temperature And Output Noise

Our mixed noise testing is described in detail here.

The first chart below illustrates the cooling fan's speed (in RPM), and the delta between input and output temperature. The results were obtained at 38 °C (100.4 °F) to 49 °C (120.2 °F) ambient temperature.   

The next chart shows the cooling fan's speed (again, in RPM) and output noise. We measured acoustics from one meter away, inside a small, custom-made anechoic chamber with internals completely covered in sound-proofing material (be quiet! Noise Absorber kit). Background noise inside the chamber was below 18 dB(A) during testing, and the results were obtained with the PSU operating at 38 °C (100.4 °F) to 49 °C (120.2 °F) ambient temperature. 

The following graph illustrates the fan's output noise over the PSU's operating range. The same conditions of the above graph apply to our measurements, though the ambient temperature was between at 28 °C (82.4 °F) to 30 °C (86 °F).  

Up to 160W load and under normal temperature conditions, the PSU's fan operates passively. Afterwards, it starts to spin briefly and and then drops to passive mode again until the load exceeds 250W. For a wide range between 250W and 550W, the fan spins at its lowest speed (805 RPM) and exceeds 32 dB(A). Maximum noise is registered with >700W loads, and it falls within the 46-49 dB(A) range. In general, Seasonic could offer a more relaxed fan profile and not compromise reliability.

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  • turkey3_scratch
    How come on the ripple page the 5VSB rail always stays under 15mv (except CL1) but on the crossloads page the 5VSB ripple graph is completely blue, hence greater than 30mv the entire time? Also, you have two "and"s in a row on Page 5. Anyway, what I love about Seasonic is they don't fall short in any category. This PSU excels everywhere, I guess except fan noise, of course.
  • BadActor
    Nice. Any chance you might have a look at the budget XT's?
  • turkey3_scratch
    2109598 said:
    Nice. Any chance you might have a look at the budget XT's?


    ^^ Yes please review one of these. Though he only reviews units that the companies actually send to him, so it could be they don't want the XT units to get reviewed, so it'd probably have to be bought retail.
  • apazeus
    I've had the 550w version since around October. At one point it was powering an FX-8350 and a 290X with no hiccups. (Nowadays it's paired with a 6600K and a GTX 1080, uses was less juice.) Nice PSUs.
  • Aris_Mp
    I cannot explain why ripple at 5VSB during the Crossload tests is higher than the high-temperature tests. This is strange indeed.

    As for the XTs I will try to find one.
  • gofasterstripes
    Lol XTR and XT - Someone call Shimano and tell them their electric groupset is looking a big fat!
  • Shankovich
    Excellent review. Could you guys possibly redo the Corsair HX 750i and up with the new review parameters? Really interested to see how it is in more detail now.
  • damric
    "All XFX PSUs are made by Seasonic"

    Not quite. These are built by Hydance.

    http://www.orionpsudb.com/news/the-mystery-of-xfx-budget-xt-line-solved-oem-and-platform-discovered
  • Aris_Mp
    When I state that a unit is made by Seasonic (or any other OEM) it doesn't necessary mean that it is made in its own factories. It is a common practice OEMs to outsource their products to other factories if they cannot meet demand (or in case they want a more affordable production line). However still the original design and the specs are set by the original designer.

    Many other models of various OEMs are also made in other factories but there is no safe way to know it without having info from the OEM itself.

    Finally, this specific article states about the XFX XT units: "If the available information is correct, XFX XT is designed by Seasonic, but the manufacturing is outsourced to Shenzhen Rui Sheng Yuan just like the Hydance. "

    As you can see there is an "if" at the beginning of the sentence. In any case, Seasonic is also behind the XT line. Given that this is an XTR review though, I thought it would be better to spare all above and just state that all XFX PSUs are made by Seasonic and not dive into such detail mentioning the outsourcing of XT line, for which there is no solid information.

    Given the opportunity I would like to mention the great work that Orion does and also thank him for the tip about the KM3S platform of the XTR-850 unit. I will try to find some details about the actual differences between the KM3 and KM3S platforms.
  • Math Geek
    i got REAL happy for second there thinking this was one of the budget XTFR units. been waiting for someone, anyone out there to review one so we can see how it performs. they are priced awesome and if they perform even average, they will be worth the low cost for mainstream pc's

    either way, nice review :) always solid work
  • turkey3_scratch
    1786133 said:
    i got REAL happy for second there thinking this was one of the budget XTFR units. been waiting for someone, anyone out there to review one so we can see how it performs. they are priced awesome and if they perform even average, they will be worth the low cost for mainstream pc's either way, nice review :) always solid work


    XTFR? Don't you mean just XT?
  • Math Geek
    yah sorry. title says XT but model number says XTFR http://pcpartpicker.com/products/compare/xfx-power-supply-p1400bxtfr,xfx-power-supply-p1500bxtfr,xfx-power-supply-p1600bxtfr/

    i tend to focus on model number since it's easier for me to keep them straight this way.
  • turkey3_scratch
    1786133 said:
    yah sorry. title says XT but model number says XTFR http://pcpartpicker.com/products/compare/xfx-power-supply-p1400bxtfr,xfx-power-supply-p1500bxtfr,xfx-power-supply-p1600bxtfr/ i tend to focus on model number since it's easier for me to keep them straight this way.


    I'm the other way around, model numbers are too hard for me to remember off the top of my head. Like if you look at EVGA';s units, nobody can remember those model numbers unless they actually study them with flash cards or have a photographic memory.