Early Verdict

Our sample died during OPP testing with 580W load, with the main fuse staying intact! This is a serious problem and till we get to the bottom of this we cannot recommend the 450 B3, although it has great performance for the standards of this category.


  • +

    Highly affordable

  • +

    Full power at 46°C

  • +

    Ripple suppression

  • +

    Load regulation

  • +

    Hold-up time

  • +

    Accurate Power Ok signal

  • +

    Silent enough

  • +

    Fully modular

  • +

    5-year warranty


  • -

    Blew during the OPP test

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    Wrong configured OPP

  • -


  • -

    Inrush current

  • -

    Not so great build quality

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    3.3V Transient Response

  • -

    Sleeve bearing fan

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    Short distance among the peripheral connectors

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    Packaging protection

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Features & Specifications

[Update, 10/13/2017: EVGA informed us that as of today all B3 units come from Superflower, not RSY]

EVGA's new B3 power supplies will succeed its B2 family, positioned between the GQ (made by FSP) and BQ (from HEC and Andyson) line-ups. The platform, shared across all B3 models, was designed by Super Flower. According to our sources, though, it's manufactured by a sub-contractor (RSY) since Super Flower's capacity is limited.

It's strange that EVGA didn't improve the B3 platform's efficiency compared to the generation prior; we still see an 80 PLUS Bronze badge. More than likely, the company wanted to keep costs as low as possible and offer something newer-sounding.

Five B3 models cover a range between 450 and 850W. The three lower-capacity members include a couple of PCIe connectors, whereas the 750 B3 has four and the 850 B3 six. None, however, come with two EPS connectors; they each have just one. In our opinion, at least the 850 B3 should have a couple of EPS connectors to support high-end motherboards.

The 450/550/650 B3 models are 150mm deep, and the 750/850 B3 versions are a little larger at 160mm.

The entry-level 450 B3 looks to be a pretty good option for budget-sensitive mainstream PCs. A $50 buy-in gets you a fully modular PSU with decent efficiency and a five-year warranty. That looks like a deal from any angle, so when EVGA was unable to provide us with a review sample, we went out and bought the whole B3 family on our own. That means the PSUs we're testing are the same ones you'll find on store shelves, guaranteed. The question of golden samples is taken care of in this case. Below is a video of our teardown of this PSU.


The PSU achieves 80 PLUS Bronze and ETA-S efficiency, while in the noise section is achieves a LAMBDA-A- (25-30 dB[A]) certification. All of its cables are modular, and it is impressive to see a selectable semi-passive mode in this price category. Unfortunately, this unit's temperature rating is lower than what the ATX spec recommends. However, $50 PSUs can get a whole lot worse, so we really can't complain much about the 450 B3's 40°C rating.

A five-year warranty is pretty good for such an affordable power supply. Further, it's nice to see all of the necessary protection features in place (at least, EVGA tells us they're there). Fifteen centimeters of depth make this a fairly compact unit. So all in all, the 450 B3 appears to be one heck of bargain. We're guessing that EVGA sells it at a small profit or none at all in order to put pressure on its competition. Corsair's more expensive CX450, in particular, is in this unit's crosshair.

The following video footage shows our work behind the scenes, demonstrating what we do to break down the PSU. More details can be found on page 3.

Power Specifications

Swipe to scroll horizontally
Max. PowerAmps202037.430.5
Total Max. Power (W)450

EVGA employs a fairly typical configuration, offering around 100W maximum combined power on the minor rails, 15W at 5VSB, and a +12V rail able to deliver the unit's full power on its own.

Cables & Connectors

Swipe to scroll horizontally
Modular Cables
DescriptionCable CountConnector Count (Total)Gauge
ATX connector 20+4 pin (600mm)1118-22AWG
4+4 pin EPS12V (600mm)1118-22AWG
6+2 pin PCIe (550mm+150mm)1218-22AWG
SATA (500mm+100mm+100mm)2618-20AWG
Four-pin Molex (500mm+100mm+100mm)1318AWG
FDD Adapter (+105mm)1124AWG

The modular cables are long enough. However, the distance between the SATA and four-pin Molex connectors should be greater than 10cm. With such short runs (especially between the four-pin Molex connectors), you might have compatibility issues if you try to use case fans installed far away from each other.

Power Distribution

Since this PSU features a single +12V rail, we do not have anything to say about its power distribution.

MORE: Best Power Supplies

MORE: How We Test Power Supplies

MORE: All Power Supply Content

Contributing Editor

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

  • InvalidError
    Throwing higher current components at a problem isn't always the correct solution, especially when a 450W PSU is delivering somewhere north of 550W. The B3's components are clearly vastly sufficient to handle its rated load or even the 580W overload, which means the most likely reasons why a FET blew up are either a design flaw or manufacturing defect and the flaw/defect isn't necessarily in the FET or its immediately related circuitry.

    In this case, it seems like EVGA/Superflower may have incorrectly set the OCP on the 12V rail. I hope they meant to set it to something more conservative like 40A instead of the 50+ it may have been at here.

    As for the main fuse not blowing, that is normal: the fuse lives upstream from the APFC choke and most other filtering components while both the APFC and main switching transistors are connected to the APFC-boosted input hold-up capacitor. The transistor's lead blows up from the capacitor dumping its several joules of energy into the lead, the APFC chokes smooth out the current spike and the current seen by the fuse comes nowhere close to reaching its i2t rating. It is the capacitor's charge that blows up the transistor, not AC input current.
  • Aris_Mp
    I strongly disagree. The main fuse has to blow when there is a short on the primary side, which clearly is the case here, else the PSU is a fire hazard if the automatic relay on the home's main electrical panel doesn't work as it should. The spark every time we connect the PSU to the mains means that high current passes through the circuit, however the fuse still remains intact. Another clue here is that our lab's relay on the electrical panel automatically dropped (saving the day), meaning that more than 15 Amps of current were drawn from this particular AC socket!! So clearly the PSU's fuse should have blown. Finally, I have seen a great number of blown PSUs so far and all have some common component failures: primary or APFC FETs, bridge rectifier(s), main fuse. In any case the main fuse has to go else the design has a serious flaw.

    Some FETs might have increased Amps on papers, however in real life things can be different especially when the high RDS (on) values increase the operating temperatures. The part though in this PSU which I am not so sure about is the bridge rectifier, since it can only handle 8 Amps at 100C and usually I see more than 100C at the bridge. So if the bridge goes up to 115-120C its max current drops close to 5A according to its spec sheet so we only have 575W handling, which is much below the 700-720W that the PSU draws from the wall with 580W load.

    The APFC choke isn't for filtering purposes, but mainly for boosting voltage, this is why it is also called boost inductor. More about how the APFC converter works and an explanation on both most popular types (DCM, CCM) can be found here: http://www.tomshardware.com/reviews/power-supplies-101,4193-10.html. I think it is pointless to explain APFC's operation here since there is an entire section about it. The bulk cap's charge didn't exactly blow the FET, the FET just couldn't handle the increased Amperage that the cap provided because of the high load. Also the bulk cap drew this load from the mains network and didn't make it out of thin air!

    Finally please don't lose sight of the forest for the trees and confuse the readers on a subject that is clear. The fuse that protects the socket into which the PSU was connected dropped, meaning that more than 15 Amps passed through it! Given that this PSU's bridge can only handle up to 8 Amps normally its fuse should be less than 8A, however it survived not once, but both times that we tried it! This clearly shows a major flaw and on the same times proves that there is a short on the PSU's primary side, which draws LOTS of current! In any case the main fuse should open the circuit in order to protect the user and the equipment from damage or even fire. The main fuse not blowing is anything else but normal! I just have to point this out
  • kalmquist
    $50 for a modular power supply seems like a great deal, even with merely Bronze efficiency. This is a good reminder not to gamble on a PSU that hasn't been reviewed by a site like Tom's Hardware.
  • InvalidError
    20089501 said:
    The APFC choke isn't for filtering purposes
    Put a 1mH APFC choke in series with a short circuit and 350V, it'll limit current rise time seen from the input side to 350A/ms, so it does filter regardless of what its other purposes in the circuit is just like any inductor would.

    I missed the paragraph about the breaker tripping. If you have RCDs or AFCI breakers, they could be tripping due to faults other than a short-circuit. If you have class-A relays, it could also be tripping faster than the fuse is able to blow.

    Edit: missing a 0... 350V/1mH = 350A/ms.
  • AndrewJacksonZA
    Is this the PSU in the video at JG of the PSU that blew up in your lab, Aris? :-)
  • 10tacle
    But we are seriously troubled by its issue and EVGA's lack of a response when we probed for possible causes.

    That is deeply troubling, especially coming from a highly reputable hardware vendor like EVGA and who I have nothing but the highest respect for (I've been buying their GPUs solely since the GTX 275).

    I sincerely hope EVGA isn't quick to get back because they are trying to find a root cause with Superflower and rule in or out a bad manufacturing batch that got past Superflower, or a bad design. I hope for EVGA it's the former.

  • Aris_Mp
    @INVALIDERROR I will try this in a circuit simulation program I have, once I find some free time.

    @ANDREWJACKSONZA If you mean about the blowing PSU in smokes, nope this is another PSU.

    @10TACLE Once we have a response from EVGA we will post it of course. To be frank I waited for a second sample from the time I notified about this problem, however I was not offered one. Also from the start EVGA didn't send any B3 samples and this is why I had to buy them on my own (given the popularity of this line), in order to check them out. With the first chance I will also buy affordable PSUs from other vendors, which usually aren't offered as review samples, in order to evaluate them.

    I would buy another 450 B3 but it is out of stock every where I searched in Europe. If I manage to find one I will try the same test again of course. Nonetheless I faced problems with other B3 models as well, which I will mention in the next B3 review.
  • AndrewJacksonZA
    OK, thank you. Keep up the good work!
  • 80-watt Hamster
    I don't find it all that surprising that they didn't shoot for a higher efficiency rating. EVGA's primary market is the US (correct me if I'm wrong), and Silver is basically a non-entity here. Bronze is the volume segment, so having a strong contender there is a necessity, and pushing it to Gold would add to an already-crowded segment of their product stack.
  • Onus
    As nasty as that blow-up might be, if used in a machine that doesn't need more than 450W, is it really a problem? Arguably, someone who tries to run a 600W PC using a 450W PSU deserves what he gets. For low-end systems, this looks like a perfectly viable choice.