Cooler Master XG850 Plus Platinum 850W Report (Page 4 of 4)

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 12W as measured by our wall meter unit, indicating that the basic load-free power consumption of the power supply is higher than normal. The extra power probably went to power its ARGB LEDs and built-in information display. Independent sources with professional load testing equipment showed the Cooler Master XG850 Plus Platinum 850W delivered excellent efficiency for its class and excellent voltage regulation and ripple across all rails. This is an 80 Plus Platinum certified power supply.

Voltages with minimal load are generally accurate, which is a basic requirement of power supplies out of the box. In this situation all are within 4%. The Power Good or PG delay is tested at 160ms, which is compatible with Non-Alternative Sleep Mode per ATX specifications. This power supply officially supports Alternative Sleep Mode, so it is likely 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 Cooler Master XG850 Plus Platinum 850W has active PFC, and the power factor will approach 0.99 with a nominal load.

The Cooler Master XG850 Plus Platinum 850W is a very quiet power supply regardless of the amount of power being drawn. Under idle level loads, the XG850 Plus Platinum is nearly inaudible, because the fan is running at only around 700 RPM. Under moderate to high loads, the XG850 Plus Platinum is still nearly inaudible, as the fan is capped at around 750 RPM. You cannot change the fan speed profile in software. Personally, I found the Cooler Master DF1352512FDHN to be exceptional. The fluid dynamic bearing fan has a smooth-running motor with no annoying noise during operation. 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 Cooler Master XG850 Plus Platinum 850W to be at 1.0/10 acoustically under typical loads. If you are a silent PC enthusiast, the Cooler Master XG850 Plus Platinum 850W is an excellent choice with its ultra-quiet and low speed fan.


The Cooler Master XG850 Plus Platinum 850W works along with a version of MasterPlus+, which is a 315MB download from the company's website at press time. This program unifies many Cooler Master products into one application, but check the website first for compatibility. Once the program opens, it will immediately detect the products you own. All settings are stored on the PSU's internal memory, so MasterPlus+ does not need to be running to maintain your custom configuration.

The main configuration window is separated into two tabs, as shown in our screenshot above. The first tab, Setup, lets you data log at a user-configurable interval. The logs will contain the fan speed, temperature, and power load at that instance in time in a text file. The second tab, Lighting, allows you to select ARGB LED lighting effects and colors, as shown in our screenshot above. Overall, I found Cooler Master MasterPlus+ to be basic, but it is very straightforward and easy to use. I do have a few complaints, which all relate to the update process. First, if a software or firmware update is available for any compatible device, you cannot launch MasterPlus+ without running the update first, which seems a bit forced. Second, the update screens all use the infamous MS Mincho Regular font and are written in poor English. I am sure Cooler Master can do better, especially for a company of this size and caliber.

Cooler Master provided this product to APH Networks for the purpose of evaluation.

Even though the Cooler Master XG850 Plus Platinum 850W is the company's first power supply made on a custom platform, they really managed to deliver a solid and innovative product. Independent test results show this 80 Plus Platinum-certified PSU delivered excellent overall performance. I am also a fan of its exceptionally low noise operation, thanks to the quiet internal fan with a very low RPM fan control profile. The real novelty of this power supply is its ARGB LED backlit built-in information display that can show fan speed, temperature, and power load. Cooler Master also includes a 10-year warranty should anything go wrong. Some suggestions for improvement include adding user-configurable fan profiles, implementing a physical button for ARGB LED effect toggling, and fixing the MasterPlus+ usability quirks. For about $260 at press time, the Cooler Master XG850 Plus Platinum is expensive for an 850W PSU, but you can be sure you are getting a performance product that is unique in a very good way.


Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests, Software, Conclusion