Kingwin Power Force 850 W Review

Name: Kingwin Power Force 850 W
Brand: Kingwin

crmaris

on Nov 25th, 2012,

in Power Supplies.

Manufacturer: Kingwin

Performance Rating & Performance per Dollar »

Ripple Measurements

You will see the ripple levels that we measured on the main rails of the PF-850 in the following table. The limits are, according to the ATX specification, 120 mV (+12V) and 50 mV (5V, 3.3V, and 5VSB).

Ripple Measurements Kingwin PF-850
Test	12 V	5 V	3.3 V	5VSB	Pass/Fail
20% Load	49.3 mV	13.7 mV	19.4 mV	11.9 mV	Pass
40% Load	59.5 mV	16.5 mV	21.0 mV	13.9 mV	Pass
50% Load	67.9 mV	18.9 mV	21.6 mV	14.4 mV	Pass
60% Load	77.1 mV	18.4 mV	22.9 mV	15.2 mV	Pass
80% Load	94.0 mV	19.4 mV	23.7 mV	19.9 mV	Pass
100% Load	106.1 mV	20.7 mV	24.3 mV	23.6 mV	Pass
110% Load	113.3 mV	21.0 mV	26.0 mV	25.8 mV	Pass
Crossload 1	39.5 mV	12.1 mV	20.9 mV	12.8 mV	Pass
Crossload 2	88.5 mV	18.3 mV	19.6 mV	16.2 mV	Pass

Ripple suppression is pretty good on the minor rails and at 5VSB; however, at +12V, the most important rail of them all, it is terrible. It took us quite some time to encounter a branded PSU with such a high ripple on this rail. Anything above 50 mV at full load starts to make us feel uncomfortable, and readings above 70- 80 mV seriously trouble us. But our scope measured above 100 mV ripple at full load with the PF-850, and such a high value is not acceptable for a modern PSU with a price-tag of over 100 bucks. Kingwin should look into this matter by making Highpower fix this problem ASAP.

Ripple at Full Load

In the following oscilloscope screenshots, you can see the AC ripple and noise that the main rails registered (+12V, 5V, 3.3V, and 5VSB). The bigger the fluctuations on the oscilloscope's screen, the bigger the ripple/noise. For all measurements, we set 0.01 V/Div (each vertical division/box equals to 0.01 V) as standard.