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 9W as measured by our wall meter unit, indicating that the basic load-free power consumption of the power supply was very good. Independent reviews from websites with professional load testing equipment showed the Corsair CX750F RGB 750W delivered very good efficiency, but voltage regulation and ripple on the +12V rail has room for improvement. This is an 80 Plus Bronze 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 all within 2%. The PG or Power Good delay is very good compared to old power supplies and within the specification of new models at 160ms.
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 Corsair CX750F RGB 750W has active PFC, and the power factor will approach 0.99 with a nominal load.
The Corsair CX750F RGB 750W is a moderately quiet power supply. Under regular loads up to 50%, the CX750F RGB is low noise. Personally, I found the Corsair NR120L to be pretty good until it ramps up. 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 Corsair CX750F RGB 750W to be at 1.5/10 acoustically under nominal loads, because the fan spins really slowly. The fan is out of the way to approximately 50% of its maximum speed, but it will become exponentially more audible when it kicks in. If you are a silent PC enthusiast, the Corsair CX750F RGB 750W is a respectable choice thanks to Corsair's good fan curve profile, but this PSU is not meant to satisfy the pickiest in noise.
Corsair provided this product to APH Networks for the purpose of evaluation.
The Corsair CX750F RGB 750W delivered very good efficiency, but voltage regulation and ripple on the +12V rail has room for improvement according to our affiliates with professional load testing equipment. Not only does this power supply have addressable RGB LED lighting, its enclosure comes in either black or white with matching color flat cables, giving the CX750F RGB a dazzling look for any tempered glass chassis. I love how its RGB LEDs can be controlled by a button at the back for those who do not have other methods to control, but Corsair also includes the right cables for those who have a compatible motherboard. A 5-year warranty is commendable for a power supply of this class. Drawbacks of the CX750F RGB comes down to a loud fan at high RPMs and mostly Teapo capacitors on the secondary side, but for about $110 at press time, the price is very reasonable for what you get.
Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion
