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 starts 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 MSI A850GF at 45c. This makes Test #1 equal to 220W by loading the 12v rails to 16a, 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 off above nominal. The efficiency for this unit is starting off in excellent shape at a value of 90.33% at 120v AC input and 89.85% at 100v AC input. We see the exhaust temperature is 48C at 120v AC input and 50C at 100V AC input.
Test #2 is equal to approximately 50% of the rated capacity of the MSI A850GF at 45c. This makes Test #2 equal to 430W by loading the 12v rails to 32a, the 5v rail to 4a, the 3.3v rail to 3a, the +5vsb to 2a, and the -12v to 0.3a. Test #2 sees across the board declines in DC output voltages relative to what we saw with Test #1. The largest changes are up to 0.04v on the 12v rails. The 5v and 3.3v rails decrease by just 0.01v. The efficiency has barely moved up to 90.71% at 120v AC input and down to 89.76% at 100v AC input. We see an exhaust temperature of 50C at 120v AC input and 52C at 100V AC input.
Test #3 is equal to approximately 75% of the rated capacity of MSI A850GF at 45c. This makes Test #3 equal to 636W by loading the 12v rails to 48a, the 5v rail to 6a, the 3.3v rail to 4a, the +5vsb to 2a, and the -12v to 0.3a. Test #3 sees slightly mixed changes. The 12v and 3.3v rails have dropped by up to 0.02v. The 5v rail has stayed even with Test #2. The efficiency in Test #3 moves down to 88.95% at 120v AC input and 87.73% at 100v AC input. We see an exhaust temperature of 54C at 120v AC input and 57C at 100V AC input.
Test #4 is equal to approximately 100% of the rated capacity of the MSI A850GF at 45c. This makes Test #4 equal to 850W by loading the 12v rails to 68a, the 5v rail to 2a, the 3.3v rail to 2a, the +5vsb to 2a, and the -12v to 0.3a. In the final regular test, we see the 12v rails mixed as they drop by up to 0.02v or rise by 0.01v. The minor rails, however, see a decrease of 0.02v each. The efficiency has dropped as we see it come in at 87.59% at 120v AC input and 86.08% at 100v AC input. We see an exhaust temperature of 56C at 120v AC input and 61C at 100V AC input.
Torture Test
The Torture Test is equal to approximately 80% of the rated capacity of the MSI A850GF at 45C. This makes the Torture Test equal to 665W by loading the 12v rails to 50a, the 5v rail to 7a, the 3.3v rail to 5a, the +5vsb to 2a, and the -12v to 0.3a. At the end of the Torture Test, theA850GF is still doing fine. 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 88.26% and the exhaust temperature is 62C.
Load Testing Summary
Today, the MSI A850GF proved to be an excellent power supply in our initial load testing. When we look at the voltage regulation, we see that the A850GF had peak changes of 0.08v on the 12v rails, 0.03v on the 5v rail, and 0.05v on the 3.3v rail. Interestingly, we have a directly comparable product with the Enermax REVOLUTION DF 850W and this unit is mixed with that unit. In addition to that, this unit is mixed with the ASUS ROG THOR 850W we reviewed some time ago. So, these absolute values are easily in the specification and this unit compares very favorably with other, similar, products.
When we look at the efficiency side of things, we see that the A850GF ranged from 87.59% to 90.71% efficient at 120v AC input and 86.08% to 89.85% efficient at 100v AC input which is excellent. Lastly, the exhaust temperature peaked at 56C at 120v AC input, 61C at 100v AC input, and 62C during the Torture Test. With excellent starting results in today’s testing, let’s move on to the Transient Load Tests.