Enermax Digifanless 550W Power Supply Review

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Ripple Measurements

The following table includes the ripple levels we measured on EDF550AWN’s rails. The limits, according to the ATX specification, are 120mV (+12V) and 50mV (5V, 3.3V and 5VSB).

Swipe to scroll horizontally
Test12V5V3.3V5VSBPass/Fail
10% Load22.3mV14.2mV14.0mV12.6mVPass
20% Load25.0mV14.5mV14.4mV13.1mVPass
30% Load24.9mV14.9mV13.9mV14.1mVPass
40% Load23.6mV14.8mV14.7mV15.2mVPass
50% Load24.8mV15.8mV15.5mV15.6mVPass
60% Load26.9mV16.0mV16.1mV15.9mVPass
70% Load29.6mV17.3mV16.5mV17.0mVPass
80% Load32.6mV18.1mV17.0mV17.9mVPass
90% Load31.2mV18.4mV18.0mV16.5mVPass
100% Load32.3mV18.7mV18.4mV19.2mVPass
110% Load33.5mV18.9mV19.2mV19.6mVPass
Crossload 140.4mV19.4mV19.2mV21.8mVPass
Crossload 219.4mV15.4mV14.2mV23.8mVPass

Ripple suppression was very good on all rails, which was not a surprise to us given the high-quality filtering capacitors that Enermax used in this unit's platform.

Ripple

The following oscilloscope screenshots illustrate the AC ripple and noise registered on the main rails (+12V, 5V, 3.3V and 5VSB). The bigger the fluctuations on the screen, the bigger the ripple/noise. We set 0.01V/Div (each vertical division/box equals 0.01V) as the standard for all measurements.

Ripple At Full Load

Ripple At 110-Percent Load 

Ripple At Cross-Load 1

Ripple At Cross-Load 2

Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.

  • blackmagnum
    If you think buying a mid-range PSU that costs as much as an enthusiast gaming CPU or graphics card, then you have more money than sense.
    Reply
  • PaulBags
    Why'd my commented get deleted? "This is a passively-cooled PSU, so you should install it with the top exhaust grille facing downward." is totally wrong advice, if you don't believe me read the warnings in the picture YOU took.
    Reply
  • Calculatron
    Ironically, I have yet to try an Enermax PSU, although I really like their other products; I have an ETS-T40-TB, a whole myriad of their fans, and the Ostrog Pink case.
    Reply
  • uglyduckling81
    "This is a passively-cooled PSU, so you should install it with the top exhaust grille facing downward. If you don’t follow this advice, hot air will be trapped inside the PSU"

    Hot air rises. If you have the opening facing down you will be trapping hot air inside. Read your own comment "top exhaust". 'Top' means on top, 'exhaust' means expulsion of air not intake.
    The PSU clearly has vents on the back and sides so I think it's a moot point either way but it's clearly a better idea to install it with the top opening facing upwards.
    Reply
  • nukemaster
    15875927 said:
    Why'd my commented get deleted? "This is a passively-cooled PSU, so you should install it with the top exhaust grille facing downward." is totally wrong advice, if you don't believe me read the warnings in the picture YOU took.
    I think your post got lost(forum bug maybe), not removed. I would see if it was removed and it was not.

    I think this would depend on the case you are using to be honest.

    System air will cool it.

    If the power supply is at the top of your system putting its vent up will cause heat to have no place to go in many cases. Power supplies in the bottom of the case would be better served with the power supply vent face up.

    The power supply has software to let you see the temperatures anyway so you can test. Tom's tests in a hotbox so it is not an actual case.
    http://www.tomshardware.com/reviews/how-we-test-psu,4042.html
    Reply
  • Aris_Mp
    guys sorry for this mistake. It is with the fan grill facing upwards and not down. This is how a single word can bring doom!
    Reply
  • Blueberries
    These are solid! I'd take a SeaSonic SS-520FL2 for $140 over this any day, though!
    Reply
  • PaulBags
    These are solid! I'd take a SeaSonic SS-520FL2 for $140 over this any day, though!
    I have the seasonic, I love it. I prefer the modular connector layout on it too, this emermax only offers a few oddly placed plugs by comparison. The cables arn't as good though, and you don't even get enough to populate all the plugs, although it's sufficent for most scenarios for a 520w PSU.

    I'd very much like to see AC cable clips become standard, I've had the ac work loose on me before when I turned a case slightly to plug something in, glad I didn't have anything important up at the time.


    To anyone who _would_ want the enermax over the seasonic I'm genuinely curious as to why. It's always good to learn and/or gain perspective.
    Reply
  • eklipz330
    i just realized my 7 year warranty for my corsair hx750 expires this year QQ
    Reply
  • f-14
    15875927 said:
    Why'd my commented get deleted? "This is a passively-cooled PSU, so you should install it with the top exhaust grille facing downward." is totally wrong advice, if you don't believe me read the warnings in the picture YOU took.
    I think your post got lost(forum bug maybe), not removed. I would see if it was removed and it was not.

    I think this would depend on the case you are using to be honest.

    System air will cool it.

    If the power supply is at the top of your system putting its vent up will cause heat to have no place to go in many cases. Power supplies in the bottom of the case would be better served with the power supply vent face up.

    The power supply has software to let you see the temperatures anyway so you can test. Tom's tests in a hotbox so it is not an actual case.
    http://www.tomshardware.com/reviews/how-we-test-psu,4042.html

    page 2 second set of pictures picture number 5 what does it specifically say? where does hotair go, where does cold air go, in a fanless case your argument is excellent advice on how to waste money and start a fire. if you are running an antec 1200 with all the fans unless this psu is mounted at the top with the vents down and all the other fans are set to intake into the case you are in great shape, however that mitigates the point of having a fanless psu, you go fanless because you don't want there to be any noise, much less a hoover vacuum for a case.

    i haven't read the warranty card, but i am sure it says something about keeping the psu vents facing up when mounted at the bottom of the case, when mounted on the side that would be interesting.

    nice psu, i will keep it in mind for the next time a customer wants a zero or low noise build.

    someday there will be a liquid cooled PSU, i laugh because of water conduction electricity, but where there is a will, there is a way to circumvent conductivity and deal with all that heat i am sure.
    Reply