Today, we're excited to delve into the intricate world of PSU testing. If you're wondering what our PSU graphs mean or how to interpret them, you're in the right place. With the launch of our new PSUCircuit channel and PSU product pages, we have many new and exciting graphs to present the data in an interesting and informative manner.
Introduction: Powering Up the Knowledge
Power Supply Units (PSUs) are the unsung heroes of every computer system, providing the necessary juice to keep everything running smoothly. Supplying power to a computer system is an extremely important step and using the wrong one could be costly. That's where our new PSUCircuit channel and PSU product pages come into play, offering a wealth of testing data and insights to guide you through the process.
Our team, led by our PSU Subject Matter Expert and Test Technicians, conducts tests to generate the data underlying the graphs you see. In this blog post, we’ll break down some of these graphs, describing how they can be interpreted and how they impact your computing experience. While this post aims to provide a basic understanding of the information presented, we encourage interested readers to do additional research for a comprehensive understanding. We will be releasing more in-depth blog posts in the future on how we conduct the testing.
The Efficiency Graphs
Efficiency is key when it comes to PSUs; a more efficient power supply will consume less energy to meet the power needs of a computer. The y-axis of our graphs represents the efficiency measurement of the power supply with a maximum of 100% which would mean the power supply is delivering all of the consumed power to the computer.
We display the 80PLUS certification requirements to provide a reference point for the efficiency ratings. However, the 80PLUS certification doesn’t always provide the full picture of a PSU’s efficiency at a variety of loads. For this reason, we conduct and graph efficiency measurements at 10% intervals of the rated load(x-axis).
The Voltage Regulation Graphs
Voltage regulation is crucial for maintaining system stability. Our voltage regulation graphs illustrate how consistent the output voltage of the PSU is across the entire load range. A perfect PSU will show a flat line, indicating consistent voltage output regardless of load. A drastic decrease in the output voltage as the load increases is an unfavorable result, and if bad enough it could cause problems as computers cannot operate properly if the supplied voltage is outside of the acceptable range. We provide color-coded sections to indicate ATX pass or fail criteria, making it easy to identify potential issues. Anything within the green section meets ATX requirements while the red section indicates points exceeding the requirements. Note that some of the output rails have different requirements.
The Ripple Noise Graphs
Ripple noise, though inevitable, can impact system performance. These graphs depict the amount of "noise" present in the PSU's output signals. A theoretical DC output will be completely steady and flat, but because this is the real world there will be some "noise". Suppose the amplitude of the noise is too high. In that case, the computer components may run into problems or completely fail to operate because the computer relies upon steady and clean power to perform optimally.
Modern power supplies typically meet the noise requirements of the components they power, but noise may become an issue if you overclock or push the hardware to its limits. Like the color-coded graphs in the Voltage Regulation section, the Ripple Noise graphs help you determine if the PSU meets ATX standards, ensuring a clean and steady power supply. Anything within the green section meets ATX requirements while the red section indicates points exceeding the requirements. While the requirements for the various output rails are lenient, they provide a good baseline to judge the power supplies against.
The Brownout Graphs
Brownouts or power dropouts can damage or cause failures in your system if your PSU isn't up to par. Our brownout tests simulate these scenarios to determine the PSU's resilience. Our test removes the input power from the power supply for a short period of time to see if it can maintain the output power and examine the reaction of the power supply in general. A power supply that is more resilient to brownouts or dropouts will be able to sustain a longer period of no or low voltage without failing to provide output power.
The sinusoidal waveform along the bottom of the graph shows the input power and the main plot shows the output voltages. The zero on the x-axis is when the start of the "brownout" is applied. The gray highlight and flat part of the input voltage show when the input power was removed from the power supply. Some power supplies will completely shut down after a power dropout, while others will drop the outputs momentarily but then "recover" to nominal output levels.
The Excursion Graphs
Excursions is a fancy ATX word for certain types of power "spikes". However, it is not actually a spike because it dwells at the increased load for a short period of time. It simulates a load requiring far above the rated load of the power supply for a very short period. An ideal power supply would be able to handle the "dynamic" excursion load without any change in voltage or ripple. A bad one will have a huge spike/drop or shut down and not be able to survive the test.
We break down the results for both 115V and 230V inputs as well as the four excursions defined in the ATX standard. The title of each graph is the time length of the excursion and the timescale of the four columns is different so that the excursion takes up the same horizontal space within the graph.
The OCP Graphs
Over-Current Protection (OCP) is vital for safeguarding the power supply and all connected components against potential faults. There are many hazardous scenarios either caused by a fault or that could lead to one. For example the power supply could have a fault causing it to increase the output voltage and damage your computer. Or a fault among one of the components of your computer could cause excessive current to be drawn from the power supply. Without the necessary protections these faults could continue unmitigated, creating shock, fire, and temperature hazards.
Our OCP graphs illustrate how each PSU responds to overload conditions. The horizontal line shows the nominal/rated current that each output rail is designed for. It is at 100% for all rails and any rails shutting down below this point are not able to achieve their rated current. The different colored bars are for 115V and 230V input. The bars are scaled by a percentage of the nominal rated load but the numbers on top of the bars are the maximum current that they were able to achieve.
There is no one "right answer" for when OCP should trigger. Triggering too low will mean that there could be cases of it happening too early when you are doing normal things, but triggering too high means that there could be a fault in the system and the OCP won't kick in because it isn't sensitive enough.
The (Coming Soon) Audio Graphs
We haven't tested any power supplies for audio yet as the audio chamber is still under construction. Stay tuned for future updates as we expand our testing capabilities to include audio graphs.
Conclusion: Powering Ahead
We're currently in the process of visualizing and will eventually make available on the website all the data we collect for power supplies. So, the graphs you see in the PSUCircuit videos and on the website only show a small fraction of the total data. We hope this blog post has shed some light on the intricacies of PSU testing data. We know there’s a lot to PSUs so we'll keep providing you with the insights you need to make informed decisions. Your computer’s performance and reliability depend on the quality of its power supply, and we’re here to help you choose wisely.
Remember, the journey to finding the perfect PSU doesn't end here. Keep an eye out for more blog posts and PSU product pages, and don't forget to subscribe to our new PSUCircuit channel for more PSU videos. Together, let's ⚡power up⚡ your computer experience.
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