Seasonic Focus GX-850 V4 ATX v3.1 PSU Review

Load Regulation

Test	12V	5V	3.3V	5VSB	DC/AC (Watts)	Efficiency	Fan Speed (RPM)	PSU Noise (dB[A])	Temps (In/Out)	PF/AC Volts
10%	5.276A	1.994A	1.981A	0.998A	85.006	86.484%	0	<6.0	49.83°C	0.952
10%	12.017V	5.016V	3.331V	5.01V	98.29	86.484%	0	<6.0	40.1°C	114.84V
20%	11.598A	2.992A	2.975A	1.202A	169.948	90.777%	0	<6.0	53.82°C	0.969
20%	11.989V	5.014V	3.328V	4.994V	187.214	90.777%	0	<6.0	40.89°C	114.81V
30%	18.263A	3.492A	3.474A	1.406A	254.943	91.15%	940	26.9	41.14°C	0.978
30%	11.985V	5.012V	3.325V	4.978V	279.697	91.15%	940	26.9	46.11°C	114.79V
40%	24.936A	3.993A	3.974A	1.612A	340.027	91.212%	936	26.7	41.83°C	0.982
40%	11.983V	5.009V	3.321V	4.963V	372.789	91.212%	936	26.7	47.2°C	114.75V
50%	31.235A	4.994A	4.973A	1.82A	424.836	90.805%	924	26.4	42.15°C	0.984
50%	11.984V	5.007V	3.318V	4.947V	467.858	90.805%	924	26.4	48.17°C	114.73V
60%	37.507A	5.995A	5.973A	2A	509.222	90.227%	915	26	42.8°C	0.986
60%	11.985V	5.005V	3.315V	4.931V	564.381	90.227%	915	26	50.39°C	114.7V
70%	43.838A	6.997A	6.976A	2.239A	594.647	89.464%	985	28.7	43.06°C	0.988
70%	11.988V	5.003V	3.312V	4.913V	664.675	89.464%	985	28.7	51.77°C	114.66V
80%	50.170A	7.999A	7.979A	2.347A	679.493	88.616%	1061	30.9	43.73°C	0.99
80%	11.991V	5V	3.308V	4.9V	766.783	88.616%	1061	30.9	53.57°C	114.64V
90%	56.899A	8.502A	8.471A	2.456A	764.96	87.736%	1140	32.9	44.52°C	0.992
90%	11.994V	4.998V	3.305V	4.887V	871.886	87.736%	1140	32.9	55.66°C	114.6V
100%	63.357A	9.006A	8.993A	3.093A	849.772	86.746%	1545	42	45.29°C	0.993
100%	11.996V	4.997V	3.302V	4.85V	979.623	86.746%	1545	42	56.76°C	114.57V
110%	69.690A	10.011A	10.093A	3.098A	934.331	85.685%	1847	51.2	46.09°C	0.994
110%	11.997V	4.994V	3.299V	4.842V	1090.414	85.685%	1847	51.2	57.42°C	114.53V
CL1	0.116A	12.021A	11.944A	0A	101.292	83.686%	944	27	40.17°C	0.959
CL1	12.029V	5.008V	3.324V	5.045V	121.038	83.686%	944	27	48.78°C	114.83V
CL2	0.115A	19.975A	0A	0A	101.369	82.716%	942	26.9	40.73°C	0.959
CL2	12.025V	5.005V	3.335V	5.05V	122.55	82.716%	942	26.9	47.3°C	114.84V
CL3	0.115A	0A	19.882A	0A	67.38	76.603%	947	27.1	40.89°C	0.947
CL3	12.020V	5.018V	3.319V	5.046V	87.962	76.603%	947	27.1	45.96°C	114.85V
CL4	70.853A	0A	0A	0A	849.491	87.534%	1334	37.4	45.15°C	0.992
CL4	11.990V	5.007V	3.312V	5.003V	970.473	87.534%	1334	37.4	55.04°C	114.58V

Load regulation is tight enough only at 5V. The 12V rail’s load regulation could be tighter if its voltage level weren’t as low at the 20W load, which is my start point at 11.907V. At 40W load, the 12V rail climbs to 12.01V. If I took the 40W load test as a reference, the load regulation at 12V would be 0.28%, which is pretty tight.

Ripple Suppression

Test	12V	5V	3.3V	5VSB	Pass/Fail
10% Load	21.0 mV	12.9 mV	13.1 mV	12.1 mV	Pass
20% Load	19.1 mV	11.9 mV	12.9 mV	10.3 mV	Pass
30% Load	14.2 mV	13.5 mV	14.3 mV	12.1 mV	Pass
40% Load	14.0 mV	13.4 mV	13.4 mV	11.5 mV	Pass
50% Load	14.6 mV	14.6 mV	14.3 mV	11.8 mV	Pass
60% Load	16.4 mV	14.1 mV	14.3 mV	12.7 mV	Pass
70% Load	16.5 mV	14.5 mV	15.0 mV	13.9 mV	Pass
80% Load	17.2 mV	16.5 mV	17.0 mV	13.2 mV	Pass
90% Load	18.4 mV	17.1 mV	17.1 mV	14.1 mV	Pass
100% Load	24.4 mV	19.1 mV	19.9 mV	15.6 mV	Pass
110% Load	23.3 mV	20.0 mV	20.6 mV	16.6 mV	Pass
Crossload 1	23.9 mV	15.4 mV	18.2 mV	14.3 mV	Pass
Crossload 2	13.7 mV	18.9 mV	18.7 mV	13.0 mV	Pass
Crossload 3	20.8 mV	14.4 mV	16.7 mV	13.3 mV	Pass
Crossload 4	24.2 mV	17.3 mV	16.4 mV	15.4 mV	Pass