Page 4 -Minor Tests and Conclusion
Power supplies are interesting products, because often, reviews of products in this category are conducted and tested in methods that make it difficult to distinguish one power supply from another. Many aspects must be taken into consideration. Certain criteria consist of efficiency, noise, power ripples, and of course the ability to pull out the rated specifications. Because many cannot afford such equipment to obtain results regarding those aspects, articles covering power supplies often come out with less than adequate and acceptable information. As this is a product report -- not a review -- what we are doing is a close examination of the power supply and the internal hardware and build. But what we can do for you is do some minor testing with the results we can present to you with and let other review sites with professional equipment show you the actual test results. We are not going to try to create useless test results by installing the power supply into the latest gaming rig and try to take readings from that, as this is not even remotely the correct way to test power supply units. We understand that many websites do that as a means of load testing, but the results, even if you use an oscilloscope and multimeter at each output location, it is not sufficient, nor does it accurately reflect the performance of the power supply.
Using our power supply tester that exerts minimal load on the power supply, the initial power consumption was 7.4W as measured by our wall meter, indicating the basic load-free power consumption of this power supply was very good. Independent tests performed by a third-party certification agency with professional load testing equipment showed the SilverStone Nightjar NJ700 700W was able to deliver excellent energy efficiency, voltage regulation, as well as the ripple performance for all rails. Keep in mind that this is an 80 Plus Titanium certified power supply unit.
Voltages with minimal load are generally accurate, which is a basic requirement of power supplies out of the box. In this situation, all are well within 4%. The PG or Power Good delay seems to be well within its rated range and general power supply standard at 310ms, but follows an older ATX specification. The ATX design specifications state a PSU's PG is required to be between 100ms and 500ms, with 250ms maximum for Non-Alternative Sleep Mode and 150ms for Alternative Sleep Mode.
Active power correction is important to correct AC load line loss. In AC power, there are three components to it since there is a phase difference between current and voltage. This makes up the power triangle, which consists of the following: Average usable power (P, measured in watts), reactive power (Q, denoted as VA-R), and total power (S, written as VA). While these are all power measurements, they cannot be considered as one thing. What we want is the average usable power with as little wasted reactive power as possible. The total power provided over the AC line is the magnitude of the two combined (sqrt(P^2+Q^2)). Power factor can now be easily calculated as P/S. The ideal value is 1.00 and this is where APFC comes in. The SilverStone Nightjar NJ700 700W has APFC, which means the power factor will approach 0.99 with a nominal load.
SilverStone Nightjar NJ700 700W is passively cooled, which means there is no internal cooling fan. Using the APH Networks noise scale that defines 0 is silent and 10 is the loudest, I could safely rate this power supply unit as 0.0/10 acoustically under any kind of load.
SilverStone provided this product to APH Networks for the purpose of evaluation.
The SilverStone Nightjar NJ700 700W is a very unique power supply unit in the market that can deliver 700W of power all without an internal cooling fan. You may not think 700W is a lot for a modern PSU, but it is impressive for a fanless one. In order to achieve the 700W output power with only passive cooling, the internal design of NJ700 features a large number of metal heatsinks and the enclosure is highly ventilated. In terms of internal component quality, there is no doubt SilverStone via Seasonic as the OEM has put some seriously good stuff into the NJ700. All capacitors are from Japan. The PCBs are well designed, and all the soldering points are nice and strong. The Nightjar NJ700 has a 5-year warranty, which is acceptable, but many premium PSUs now come with a 10-year or longer warranty now. The NJ700 is $320 USD at press time. This is a good buy if you can find it at a more competitive price, as the virtually identical Seasonic PRIME FANLESS TX-700 700W is only $265 with a 12-year warranty.
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion