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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.

EVGA 750 B3

Bitfenix BWG750M

Corsair CX750M

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 750 B3's power-good signal is accurate.

Inrush Current

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

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The inrush current is at normal levels with 115V input, but it's quite high at 230V.

Load Regulation And Efficiency Measurements

The first set of tests reveals the stability of the voltage rails and the 750 B3'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 #	12V	5V	3.3V	5VSB	DC/AC (Watts)	Efficiency	Fan Speed	PSU Noise	Temps (In/Out)	PF/AC Volts
1	4.385A	1.984A	1.984A	0.985A	74.767	78.388%	0 RPM	<6.0 dB(A)	42.57°C	0.956
1	12.127V	5.050V	3.320V	5.060V	95.381	78.388%	0 RPM	<6.0 dB(A)	38.14°C	115.19V
2	9.808A	2.971A	2.981A	1.188A	149.737	82.908%	1180 RPM	26.7 dB(A)	40.01°C	0.982
2	12.120V	5.044V	3.317V	5.042V	180.607	82.908%	1180 RPM	26.7 dB(A)	44.56°C	115.19V
3	15.583A	3.479A	3.496A	1.391A	224.879	85.474%	1218 RPM	27.3 dB(A)	40.19°C	0.989
3	12.114V	5.039V	3.314V	5.025V	263.096	85.474%	1218 RPM	27.3 dB(A)	44.85°C	115.20V
4	21.355A	3.977A	3.983A	1.595A	299.740	86.755%	1240 RPM	27.8 dB(A)	40.40°C	0.992
4	12.107V	5.035V	3.311V	5.005V	345.503	86.755%	1240 RPM	27.8 dB(A)	45.39°C	115.19V
5	26.802A	4.974A	4.986A	1.803A	374.721	86.934%	1315 RPM	30.4 dB(A)	40.85°C	0.994
5	12.097V	5.030V	3.307V	4.985V	431.041	86.934%	1315 RPM	30.4 dB(A)	46.07°C	115.19V
6	32.255A	5.975A	5.991A	2.010A	449.621	86.672%	1425 RPM	32.3 dB(A)	41.39°C	0.995
6	12.086V	5.024V	3.303V	4.965V	518.762	86.672%	1425 RPM	32.3 dB(A)	46.64°C	115.19V
7	37.723A	6.982A	6.996A	2.222A	524.620	86.079%	1518 RPM	35.4 dB(A)	42.14°C	0.996
7	12.075V	5.019V	3.300V	4.944V	609.464	86.079%	1518 RPM	35.4 dB(A)	47.49°C	115.22V
8	43.204A	7.984A	8.010A	2.435A	599.523	85.391%	1645 RPM	37.4 dB(A)	42.86°C	0.996
8	12.062V	5.012V	3.295V	4.923V	702.091	85.391%	1645 RPM	37.4 dB(A)	48.44°C	115.19V
9	49.128A	8.487A	8.535A	2.440A	674.581	84.523%	1796 RPM	41.4 dB(A)	44.65°C	0.996
9	12.050V	5.009V	3.292V	4.910V	798.101	84.523%	1796 RPM	41.4 dB(A)	50.49°C	115.19V
10	54.814A	9.002A	9.050A	3.078A	749.458	83.619%	1910 RPM	42.1 dB(A)	45.68°C	0.996
10	12.036V	5.004V	3.281V	4.866V	896.273	83.619%	1910 RPM	42.1 dB(A)	51.81°C	115.19V
11	61.100A	9.012A	9.065A	3.085A	824.374	82.633%	2014 RPM	43.1 dB(A)	47.08°C	0.997
11	12.024V	4.998V	3.275V	4.855V	997.629	82.633%	2014 RPM	43.1 dB(A)	53.48°C	115.18V
CL1	0.098A	14.027A	14.003A	0.004A	117.483	75.801%	1425 RPM	32.3 dB(A)	44.06°C	0.977
CL1	12.119V	5.027V	3.268V	5.087V	154.989	75.801%	1425 RPM	32.3 dB(A)	49.72°C	115.20V
CL2	62.446A	1.003A	1.002A	1.002A	764.673	83.995%	1945 RPM	42.1 dB(A)	46.78°C	0.997
CL2	12.032V	5.013V	3.287V	4.991V	910.382	83.995%	1945 RPM	42.1 dB(A)	52.70°C	115.19V

Load regulation is fairly tight on all of the rails except for 5VSB, which is worth noting from a budget-oriented platform. Meanwhile, the 750 B3 delivers full power at very high ambient temperatures (>45°C) without breaking a sweat. Its output noise remains low until the 50% load test, after which it exceeds 30 dB(A) during the sixth test and more than 40 dB(A) from the ninth test and up. Generally, though, the fan profile isn't that aggressive, considering this is a relatively low-efficiency PSU.

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Aris Mpitziopoulos

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

9 Comments Comment from the forums

Dark Lord of Tech

Several complaints in the forums from builders , very disappointed with the B3 series.
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logainofhades

Yea, I will no longer recommend a B3 series PSU. Seasonic and Corsair's new CX450m-650m are better options right now.
Reply
SinxarKnights

The solder quality between review samples and retail samples is pretty shady in of itself IMO.
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10tacle

The fact that EVGA hasn't even responded to the 450W B3 fail test that was back in August is highly disturbing in an of itself. It is inexcusable to just ignore a tech website's inquiry (and serious concerns) as to why a series of their products are failing. I know EVGA's customer support is top notch in the industry (I've had to use it), but their public/customer relations team needs an overhaul. If I were the CEO, I'd be calling for some heads and light a fire under some backsides to ride Super Flower hard for a fix.
Reply
maxwellmelon

with out them identifying the failed component how can they say that the PSU not turning back on after a OPP is not intentional setup because it being shut down at 120% of load is about right like they said. It could be designed that way as a safety feature. and a way to sell more psu because when you try to RMA it they can say you overloaded it and is not covered. Operating above 750 watts is above the psu limits and having a one time OPP shut down is still technically having OPP on it.
Reply
Aris_Mp

When a PSU is broken after OPP's triggering, it is not a feature but a problem. OPP along with the rest of the protections is there to protect the PSU in order not to break when a user goes wild with it.
Reply
Lutfij

The third paragraph of the last page reminded me of what cars with all souped up aftermarket parts but a crappy driver often results with - disaster.

EVGA Have recently come under flack on other forums as well and their response isn't, erm, admirable. Nice work with the review, Aris, keep it up!
Reply
rtansey378

They must be having issues in the CS department. After dealing with them for an RMA I found their website to be down totally twice and fundamentally broken in important other areas during RMA submission. I was getting different answers from different people to basic questions and there were unreturned emails that led to other issues - it was kind of a nightmare overall that went on for a month. Even after being expedited to a manager of some type it wasn't much better. And their 2-3 advance RMA uses UPS ground so it is not 2-3 days at all. It routinely takes them 3 days to get the replacement into UPS' hands and then UPS takes their sweet time. People also use their expensive desktop PCs for work. I went through that twice as they sent the wrong unit back the first time.

They charge a premium largely on their CS reputation. I guess they are now hoping people won't have to use it and learn otherwise. Being branded as a good guy in the CS is huge. Being branded as a bad guy is a death sentence. You'd think they would at least return major website emails and spin use some good old corporate spin. They won't even do that. Makes you wonder.

I hope they figure it out. But Im no longer going to pay their premium. If they have the cheaper product then I would still consider them. That will rarely be the case. They did some nice patented stuff with their GTX 1070/1080 revisions so maybe they are putting all their eggs in that basket.
Reply
mlee 2500

Wow, I expect better from something EVGA puts their name on.

THANK YOU tom's HARDWARE for performing objective tests on multiple samples to keep us informed and the vendors honest....

I seriously could have seen myself buying my next PSU based on EVGA's reputation alone. I won't make that that mistake now.
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