Testing:

The testing of this power supply will take on a format used only twice so far at Bigbruin.com. Instead of testing the power supply in a computer, the gear to be used for this review consists of four dynamic DC loaders (two rated for 300W each, and two rated for 750W each), a 4-channel USB data logger, a digital multimeter, a 2-channel digital thermometer, a digital infrared thermometer, an AC power monitor, and a heat source. A brief description of each item's purpose is provided below...



The DC loaders will be split up to handle the loads on the main power rails. Due to limitations that prevent the 300W units from being useful down to 3.3V, a somewhat inefficient distribution of power has to be implemented. One 300W unit will handle the 5V rail, the other 300W unit will handle a 12V rail, one of the 750W units will handle the other five 12V rails, and the other 750W unit will get to take it easy while handling just the 3.3V rail. Since there are six 12V rails and just two 12V loaders at this point, rails obviously have to be joined together. -12V and +5VSB will not be considered.

The 4-channel USB data logger is like an oscilloscope, and the channels will be used to monitor and log voltage data on the 3.3V, 5V, and 12V rails. In the first review published with this setup I discovered that the data logger only goes to two decimal places, making ripple readings down to single digits in terms of milliVolts impossible. Instead, results will be reported in terms like "< 10mV" or "< 30mV", where I can only really say the value was less than 10 or 30mV, for example. Later I discovered that the sampling frequency is slower than I had first thought, so that is another factor to consider in analyzing the data acquired. The PSU testing lab has been effectively shut down for the Winter with this review, and in the Spring I will look into an upgrade.

The digital multimeter is mostly for confirmation and setup.

The 2-channel digital thermometer is for monitoring the PSU inlet and outlet temperatures.

The digital infrared thermometer is for setup purposes and for checking the temperatures of cables and other surfaces to make sure nothing melts or burns. Melting and burning is obviously not welcome, and after running into more than my fair share of it in an earlier review, I not only lost privileges at my initial test spot (my basement office), but I also check things far more frequently! Needless to say, I was banished to the garage and it is just too cold to 'play' out there right now, so after this PSU review it might be a while until the next one.

The AC power monitor will have the PSU plugged in to it in order to monitor the AC Wattage to be compared to the DC Wattage to calculate an efficiency value).

The heat source is a compact ceramic space heater with variable controls that is about the size of a power supply. It will be used for testing at elevated temperatures.

The power supply will be tested at a few steps between minimum and maximum power, and the results will recorded at each step along the way. This will be done with the power supply drawing in ambient temperature air (which was approximately 18C), and later with the heat source being used to maintain an inlet temperature between 30C and 40C (temperature was regulated by varying the proximity to the heat source). The specifications details a MTBF of 100,000 hours at 25C, and that it is rated for 1000W continuous service at 50C. There is a bit of disparity between the two statements in my opinion, and while we won't have long term data to present in this review, it will be interesting to see how hot it might get.