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 which exerts minimal load on the power supply, the initial consumption was 7W as measured by our wall meter unit, indicating that the basic load-free power consumption of the power supply is very good. Independent sources with professional load testing equipment showed the be quiet! Dark Power 13 850W delivered very good efficiency for its class and good voltage regulation and ripple across all rails. This power supply unit has 80 Plus Titanium and Cybenetics ETA Titanium ratings.
Voltages with minimal load are accurate, which is a basic requirement of power supplies out of the box. This power supply is ATX 3.0 compliant and officially supports Alternative Sleep Mode with 100 to 150ms PG specifications, so it looks like the PSU tester I used was not fast enough to pick up the true PG signal. 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, as 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 they all have the same physical units, it is not the same thing as aforementioned. 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 then be easily calculated by P divided by S. The ideal value is 1.00, and this is where active PFC comes in. The be quiet! Dark Power 13 850W has active PFC, and the power factor will approach 0.99 with a nominal load.
The be quiet! Dark Power 13 850W is a very quiet power supply. The 850W Dark Power 13 is barely audible pretty much across the entire range. Personally, I found the Silent Wings BQ SIW3-13525-HF fan to be excellent, living up to the name of the brand. While this is very subjective, I am quite a picky person on noise. On a scale from 0 to 10 where 0 is silent and 10 is the loudest, I would rate the be quiet! Dark Power 13 850W to be at 1.0/10 acoustically under nominal loads, because the fan is not only acoustically optimized to begin with, but also spins really slowly. It is too bad it does not have a fan-stop feature, but this is as close as it gets. The fan is basically out of the way even when the load increases, but as with all fans, it will become more audible as it spins faster. This PSU is rated at Cybenetics LAMBDA A++ for noise, which is the highest tier. If you are a silent PC enthusiast, the be quiet! Dark Power 13 850W is a very respectable choice thanks to the PSU's acoustics-optimized design and ultra-quiet fan curve profile.
be quiet! provided this product to APH Networks for the purpose of evaluation.
The be quiet! Dark Power 13 850W is a top-spec PSU with Titanium-grade efficiency certifications while highly optimized for minimal noise. Even though there is no semi-fanless mode, the acoustically optimized air intake and fan design along with a super quiet fan curve will satisfy the pickiest of users. Internally, it is built on a high-end FSP platform with a very good selection of components, including 100% Japanese-made capacitors. Furthermore, it is ATX 3.0 and PCIe 5.0 compliant for all your latest hardware. According to others with professional load testing equipment, the be quiet! Dark Power 13 850W delivers acceptable performance. Drawbacks of the Dark Power 13 850W comes down to a multiple 12V rail design uncommon in modern power supplies. You can combine them by an included expansion slot switch panel or jumper, but I feel like this is unnecessary in 2023. For about $250 at press time, the be quiet! Dark Power 13 850W fulfills its mission of being an ultra-quiet, ultra-efficient power supply with the latest certifications and a 10-year warranty to back you up, but it is not light on the wallet.
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion