Efficiency, According to the 80 PLUS Specification


Efficiency Across the Power Spectrum


The 80 PLUS Bronze efficiency requirements aren't as stringent. So, while the SST-ST50NF does meet the organization's Bronze-level requirements, its efficiency value at low loads is far worse than the values recorded from the other two contenders. At 25 W, its efficiency is only 60%. With that said, it behaves like a typical Bronze-certified power supply, and does not stand out negatively among other Bronze-level supplies.
Unfortunately, the same cannot be said about the ripple voltage on its +12 V rail. At 129 mV, it does not even comply with ATX standards.
On the positive side, the SST-ST50NF sports an above-average hold-up time of more than 40 ms. The Nightjar power supply passes all other tests with flying colors. We measured a temperature increase of 49 degrees Fahrenheit, which is slightly less than the temperature increase of the Seasonic supply. Also, we're fans of the warning LED on the back of the power supply that warns of critical internal temperatures (though we're not sure you'd see it light up behind your PC).
A Peek at the PCB
The first thing we noticed after opening SilverStone's SST-ST50NF was its massive heat sinks covering large parts of the circuit board. This is a stark contrast to the Seasonic X-460.
Obviously, the dramatically larger heat sinks are necessary in light of the Nightjar's lower efficiency rating. At an identical load, it'll dissipate more heat than the 80 PLUS Gold-certified Seasonic unit. We can also see that the SilverStone supply has a well-designed input filter, unlike some low-cost solutions. SilverStone also uses premium-grade components, like Chemi-Con capacitors from Japan and Infineon MOSFETs. Instead of a single high-capacitance capacitor on the primary circuit, four smaller ones are used in parallel, which increases the surface area and thus aids in cooling. Copper shims between the power transistors and the large heat sink also serve to improve cooling.
The manufacturing quality of this fanless supply is impeccable, and the quality of the electronic parts is top-notch as well. However, the out-of-tolerance ripple voltage does raise questions about the electrical quality of this power supply. When we factor in the lower price and higher efficiency of competing models, like Seasonic's X-460, we find it difficult to recommend the fanless solution from SilverStone.
- Two Fanless Power Supplies, Compared
- be quiet! Straight Power E9 CM 480 W
- Measurements: be quiet! Straight Power E9 CM 480 W
- Seasonic X-460 460 W
- Measurements: Seasonic X-460
- SilverStone SST-ST50NF
- Measurements: SilverStone SST-ST50NF
- Test Setup, Hold-Up Time, Inrush Current, Peak Load, And Short Circuit Protection Test
- Efficiency According To The 80 PLUS Spec, Temperature, And Standby Power
- Efficiency Across The Power Spectrum
- Which Fanless PSU Is Right For You?


Last time I checked, Americans aren't the only ones who enjoy a silent computing experience...
Many companies that are focused on silence such as Noctua and beQuiet! are not "American."
I think it is quite neat that they have fanless option. I would never take the risk, but if I did I would chose seasonic, my 750W has done me well.
Last time I checked, Americans aren't the only ones who enjoy a silent computing experience...
Many companies that are focused on silence such as Noctua and beQuiet! are not "American."
--> argument over.
For the record I am not an American and I don't live in the US
I've been buying Corsair and even $45 Thermaltake 500... and I cannot hear them... with the cover open. The problems with FANLESS PSUs and GPUs is that they become heat-sinks... sure they are quiet, but everything around them gets warm. You need to blow the hot air out.
Going from a fanless GPU to something with a huge fan (H.I.S. brand) - the fans barely makes noise and use a rear exhaust and I can run the system fans at a lower speed.
Mitko: get soundproofing material, apply to inside of case. Put case on floor.
My case is on the desk, a foot or so away from me... its no louder than the A/C vent blowing air in the room.
1. The heat stress is the factor No. 1 for the lifespan of the capacitors, no matter if they are conductive polymer or very high quality electrolytic brand.
2. The case should use more higher intake flow to make sure that the power supply's heat does not enter the case.
3. A noise level of 10-13 dB can be tolerated for the sake of sustainability and avoiding the risk of heating up your case with the heat from from the PSU.
Personally, in the last 10 years I admire Seasonic for their stile... But I would use a passive solution that is still in the PC case just for a while.
most of the voltage regulators are mostly the same though they may add a larger heatsink on them.
you could pretty much turn a standard PSU into a silent one by swapping the caps and heatsinks. High quality capacitors are about 3-5 times more expensive (may take the cost of a single cap from 5 cents, to around 15-20 cents)
Yeap, and you get a better, more reliable, energy efficient bit of kit too. Bit I don't think I'll be having a go a swapping them
Not an 'American' thing, but a medical one. Noise pollution is becoming more and more of a problem; and affects long term hearing quality.
No wonder people can no longer hear the difference between an MP3 and a CD recording.
Every now and then you can find it on sale for $120. A steal for the best 650W PSU in the world.
it'll be used in an HTPC/home media server. to those that have doubts about the usefulness of such a PSU, I will ask: "what's the point of having that nice audio system in your living room if all you're gonna hear is fan noise in the background?"
Another article is what got me hooked http://www.silentpcreview.com/Seasonic_X-400_Fanless_PSU, they basically had to resort to a hair dryer to make the thermal protection trip. A very good power supply that can put up with alot of heat before having to shut down.
translate please...don't understand...thanks in advance