Load Testing
For those of you that are curious as to some of the reasoning and equipment behind our PSU testing program here at TheFPSReview, we have put together an introduction for you. This program is based on what the author developed at [H]ardOCP and utilizes the equipment bequeathed to the author by Kyle Bennett. The testing we are conducting today is exactly as described in that document and start with our 120v, 100v, Torture, and 80 Plus Tests.
120v and 100v Load Testing Results
Test #1 is equal to approximately 25% of the rated capacity of the SilverStone SX750 at 45c. This makes Test #1 equal to 184W by loading the 12v rail to 13a, the 5v rail to 2a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. The results of Test #1 show the main positive DC output rails starting above nominal. The efficiency for this unit is starting off in excellent shape at a value of 90.28% at 120v AC input and 89.75% at 100v AC input. We see the exhaust temperature is not currently registering due to the fan controller.
Test #2 is equal to approximately 50% of the rated capacity of the SilverStone SX750 at 45c. This makes Test #2 equal to 367W by loading the 12v rail to 27a, the 5v rail to 4a, the 3.3v rail to 2a, the +5vsb to 2a, and the -12v to 0.3a. Test #2 sees drops in the DC output voltages relative to what we saw with Test #1. The largest changes are up to a 0.06v increase on the 12v rail followed by a 0.01v drop on the 5v rail and 3.3v rail. The efficiency has moved up to 93.93% at 120v AC input and 93.21% at 100v AC input. We see an exhaust temperature of 49C at 120v AC input and 51C at 100V AC input.
Test #3 is equal to approximately 75% of the rated capacity of SilverStone SX750 at 45c. This makes Test #3 equal to 573W by loading the 12v rail to 42a, the 5v rail to 7a, the 3.3v rail to 5a, the +5vsb to 2a, and the -12v to 0.3a. Test #3 sees the 5v and 3.3v rails drop by 0.02v and 0.03v respectively. The 12v rail has decreased by up to 0.02v. The efficiency in Test #3 moves down to 92.03% at 120v AC input and up to 91.00% at 100v AC input. We see an exhaust temperature of 52C at 120v AC input and 55C at 100V AC input.
Test #4 is equal to approximately 100% of the rated capacity of the SilverStone SX750 at 45c. This makes Test #4 equal to 752W by loading the 12v rail to 60a, the 5v rail to 2a, the 3.3v rail to 1a, the +5vsb to 2a, and the -12v to 0.3a. In the final regular test, we see all of the main DC output voltages drop by up to 0.01v. The efficiency has dropped as we see it come in at 88.47% at 120v AC input and 87.04% at 100v AC input. We see an exhaust temperature of 55C at 120v AC input and 60C at 100V AC input.
Torture Test
The Torture Test is equal to approximately 80% of the rated capacity of the SilverStone SX750 at 45C full load. This makes the Torture Test equal to 606W by loading the 12v rail to 44a, the 5v rail to 8a, the 3.3v rail to 6a, the +5vsb to 2a, and the -12v to 0.3a. At the end of the Torture Test, the SX750 is still doing well. The DC output voltages are generally in line with what we have been seeing in the 120v load tests. The efficiency is excellent as we see a value of 90.13% and the exhaust temperature is 63C.
80 Plus Load Testing Results
As we see here, the SilverStone SX750 posts efficiency values of 89.18%-90.23%-87.32% using 80 Plus’ load testing parameters. This puts the WAY under the 80 Plus Platinum standard across the board. However, we do use different equipment than 80 Plus for our testing and there is always a bit of component variation.
Load Testing Summary
Much like the SilverStone SX700-G and SX700-PT before it today, the SilverStone SX750 did a very good job in our initial load testing. When we look at the voltage regulation, we see that the SX750 had peak changes of 0.04v on the 12v rail, 0.04v on the 5v rail, and 0.05v on the 3.3v rail. These absolute values are easily in the specification and better than anything we have seen from previous SFX offerings while being larger in capacity to boot! On top of that, they would be simply awesome even in a larger ATX12v/EPS power supply!
However, this unit did stumble quite badly when it came to efficiency. True it posted a range of 88.47% to 93.93% efficient at 120v AC input and 87.04% to 93.21% efficient at 100v AC input. When it came to the 80 Plus numbers, though, this unit missed, and missed badly, as it was 89.18%-90.23%-87.32% efficient. These are 80 Plus Gold numbers, not 80 Plus Platinum numbers and, beyond that, on the high end of its range, this unit was less efficient than previous SilverStone SFX units. Lastly, the exhaust temperature peaked at 55C at 120v AC input, 63C at 100v AC input, and 61C during the Torture Test. With very good starting results in today’s testing, let’s move on to the Transient Load Tests.