NZXT E Series 850W PSU Review: An Analog Platform With Digital Enhancements

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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.

Hold-Up Time

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

NZXT's hold-up time is 2ms longer than what the ATX specification requires, while the power-good signal is accurate (but lower than 16ms).

Inrush Current

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

Measured inrush current is on the high side, especially with 230V.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the E850’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.

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Test #12V5V3.3V5VSBDC/AC (Watts)EfficiencyFan SpeedPSU NoiseTemps (In/Out)PF/AC Volts
15.262A1.988A1.972A0.981A84.912 (71)86.212%590 RPM10.4 dB(A)40.31°C0.975
211.513A2.983A2.960A1.179A169.409 (154)89.911%956 RPM24.4 dB(A)40.86°C0.985
318.165A3.481A3.439A1.379A254.492 (238)90.771%1245 RPM32.4 dB(A)41.07°C0.987
424.819A3.978A3.951A1.580A339.677 (321)90.748%1598 RPM37.4 dB(A)41.57°C0.988
531.147A4.976A4.939A1.781A424.992 (402)90.362%1907 RPM41.3 dB(A)42.18°C0.988
637.409A5.971A5.930A1.984A509.510 (485)89.840%2162 RPM43.9 dB(A)42.85°C0.988
743.740A6.967A6.922A2.188A594.815 (569)89.235%2162 RPM43.9 dB(A)43.26°C0.989
850.075A7.962A7.917A2.392A680.169 (651)88.573%2187 RPM43.9 dB(A)43.74°C0.990
956.805A8.462A8.399A2.395A765.087 (734)87.855%2171 RPM43.9 dB(A)44.40°C0.991
1063.265A8.958A8.910A3.006A849.906 (814)86.874%2175 RPM43.9 dB(A)45.56°C0.991
1170.319A8.962A8.913A3.010A934.678 (897)84.656%2179 RPM43.9 dB(A)46.80°C0.992
CL10.144A12.004A11.998A0.000A102.225 (110)83.899%1766 RPM39.7 dB(A)42.38°C0.983
CL270.024A1.002A1.002A1.000A854.131 (828)87.398%2171 RPM43.9 dB(A)45.31°C0.991

Load regulation is super tight, though it's merely decent at 5VSB. We're most disappointed in NZXT's aggressive fan profile, which results in lots of noise even though we chose Silent mode in the CAM software. If you want the E850 to be quiet under high temperatures, consider creating a custom fan profile instead.

The E850's efficiency is high, easily satisfying the 80 PLUS Gold specification's requirements with 20% and 50% load. Although it falls short under full load, we do test at much higher temperatures than the 80 PLUS organization, so efficiency naturally takes a hit.

The bracketed DC wattage readings are the ones we observed in NZXT's software.

NZXT CAM Software Screenshots

We took a number of screenshots from the CAM software and compiled them into an album.

The DC power readings are not accurate. Neither is the voltage information.

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Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.