Testing

To test the power supply unit, we will not connect it to an everyday system as we would be unable to know the exact load that we would provide and wouldn’t be able to vary the load. Instead we will use power resistors which are nothing more than normal resistors but capable of consuming a good amount of power. How much power depends on the resistance and capability of the resistor, and can be easily calculated by Ohm’s law (Amperes = Voltage / Resistance, Power = Voltage * Amperage).

Hence for example a 1Ohm resistor attached to the 3.3V line will allow 3.3A through it and consume about 10W of power. When adding two of these resistors in parallel, you double the power consumption and allow 20W to be consumed as you halve the resistance this way. Adding more will increase the power consumption. Of course that is not entirely accurate on paper as the fault tolerance of these resistors is high and almost none are exact to their resistance specifications, but after using them we could calculate how much power each bunch of them would consume accurately. This way we can add fake load to any power supply unit, and on any power line we wish with good accuracy.

For testing the X-Connect VS 700W unit, taking into account its design and power specifications, we took the following steps:

Total Load	3.3V Load	5V Load	12V Load
33% (~220W)	15A (50W)	10A (50W)	10A (120W)
50% (~340W)	25A (83W)	15A (75W)	15A (180W)
75% (~480W)	25A (83W)	20A (100W)	25A (300W)
87% (~620W)	28A (90W)	25A (125W)	34A (408W)

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The room temperature when the test took place was 25 Celsius degrees. The unit has a single 12V line, so in order to load it we broke our resistors in several small groups, because trying to pull 400W+ of power out of a single cable would most likely be impossible, if not damage it. The highest stable output we managed to squeeze out of the X-Connect VS unit was 87% of its rated full load. Unfortunately just a few more Watts and the power supply unit would shut down after a few minutes, if not seconds. Also, the X-Connect VS was admirably silent up to 50% load, audible but tolerable at 75% load, but very loud and hot when loaded over that. It also seemed to weaken when loaded above 85% of its capacity.