EVGA 450 BT PSU Review: Amazing Value At $25

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EMC Pre-Compliance Testing

EMC, EMI & EMS Acronyms

Electromagnetic Compatibility (EMC): The ability of a device to operate properly in its environment without disrupting the operation of other close-by devices.

Electromagnetic Interference (EMI): This represents the electromagnetic energy a device emits, which can cause problems in other close-by devices if it is too high.

Electromagnetic Immunity (EMS): Tolerance to electromagnetic emissions.

Equipment & Standards

To properly measure the EMI that a device emits, you need special equipment defined by the CISPR 16-1-1 specification. To learn more about our EMI testing equipment, please check out How We Test Power Supply Units.

In order to minimize EMI noise, some standards have been established. The corresponding standards for Information Technology products are CISPR 32 and its derivative EN 55032. In the EU, every product featuring the "CE" marking has to comply with EN 55032. Both CISPR 32 and EN 55032 divide devices into two classes, A and B. B-class equipment is for domestic environments, so its allowed EMI emissions are significantly lower than for A-class devices.

Swipe to scroll horizontally
CISPR 32 / EN55032 Limits
CISRP 32/ EN 55032 Class A Conducted EMI Limit
Frequency of Emission (MHz)Conducted Limit (dBuV)
Quasi-peakAverage
0.15 - 0.507966
0.50 - 30.07360
CISPR 32/ EN 55032 Class B Conducted EMI Limit
Frequency of Emission (MHz)Conducted Limit (dBuV)
Quasi-peakAverage
0.15 - 0.5066 - 5656 - 46
0.50 - 5.005646
5.00 - 30.006050

EMI Results - Average Detector

Although there a number of spikes in this chart, the 450 BT still passes the average detector test without any significant problems.

EMI Results - Peak Detector

The same goes for our peak detector test: EVGA's 450 BT passes without a problem.

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Contributing Editor

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

  • Onus
    This looks like a decent choice for a business-class PC, or even a light gamer, which probably won't pull more than half its rated output.
    Reply
  • chimera201
    Could you measure hold up at lower loads(20%, 50%, etc)?
    And why isn't inrush results included in cybenetics database?
    Normally "S" is considered higher than "A++"
    Reply
  • Aris_Mp
    S stands for standard. As for the hold-up time, it is measured only in the worst case scenario, which is full load. Unfortunately there is no time to take extra measurements, especially since we want to implement some other tests.

    About the inrush current, Cyben''s pdf report covers only the basic in order to be kept at a normal size.
    Reply
  • chimera201
    Just curious how the values for hold up would look like at lower loads (I know it's higher). If you do plan on testing it even once at-least do it on a cheaper PSU unit. Testing it on a higher-end unit would defeat the purpose.

    And I thought Cybenetics was supposed to give a detailed report. Not including inrush results, etc kind of defeats the purpose.
    Reply
  • Aris_Mp
    The main role of Cybenetics is to provide efficiency and noise certifications. The extra results are just to let people know a little more about a PSU's quality. If Cyben provided everything then it would be a review and not a certification.
    Reply
  • HERETIC-1
    Quality,low power PSU's are hard to find-Reason-Quality components cost money.
    PSU IS THE MOST IMPORTANT PART OF ANY BUILD.....................
    RECOMENDED-
    Seasonic G360 or G450
    Corsair SF450
    Reply
  • Marlin Schwanke
    Read the list of cons again. This thing is junk. There is no such thing as a decent $25 power supply.
    Reply
  • fry178
    so more cons than pros, calling it decent build quality when almost all cons are related to quality.
    lol.
    less respect with every review like this..
    Reply
  • Aris_Mp
    Every product is judged based on its price.

    "Almost all cons are related to quality". Actually two our of the six have to do, in a degree, with build quality. Thin cables and overated MOV. Transient response, lower hold-up time, noise and old platform are not build quality related. Build quality has to do with the quality of the components and the craftsmanship unless you imply/understand something else.

    You know what I also call decent build quality? A PSU that has a 25C rating and manages to finish all of my tests at much higher ambient temperatures. If its components were crappy then it wouldn't even last a minute under the overload tests, as many other PSUs that have died in my hands so far.
    Reply
  • fry178
    cables are still components.
    and as well as everything else, it's still directly/indirectly related to quality, no matter if physical parts or design/engineering.
    especially since this isnt a box sold by a 12y living in the grandparents basement.

    i dont expect a semi modular unit with a 140mm silent fan on this, but i doubt lots of ppl would consider this type of "quality" product, if it was anything else they are using, not even talking about the fact its a name brand that sells very good units.


    when did it start to be ok for a product to have more cons than pros?...
    doesnt make any sense to me to call it "amazing value".
    but i guess thats just me.

    Reply