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 Lian Li SP750 at 45c. This makes Test #1 equal to 183W 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 89.36% at 120v AC input and 88.93% at 100v AC input. We see the exhaust temperature is 47C at 120v AC input and 50C at 100v AC input.
Test #2 is equal to approximately 50% of the rated capacity of the Lian Li SP750 at 45c. This makes Test #2 equal to 368W 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 0.02v decrease on the 12v rail and 5v rail followed by a 0.01v drop on the 3.3v rail. The efficiency has moved up to 90.38% at 120v AC input and 89.72% at 100v AC input. We see an exhaust temperature of 49C at 120v AC input and 52C at 100V AC input.
Test #3 is equal to approximately 75% of the rated capacity of Lian Li SP750 at 45c. This makes Test #3 equal to 568W 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 stay even with Test #2. The 3.3v rail drops by 0.03v. The 12v rail has decreased by up to 0.07v. The efficiency in Test #3 moves down to 89.06% at 120v AC input and 87.15% 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 Lian Li SP750 at 45c. This makes Test #4 equal to 746W 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 54C at 120v AC input and 59C at 100V AC input.
Torture Test
The Torture Test is equal to approximately 80% of the rated capacity of the Lian Li SP750 at 45C full load. This makes the Torture Test equal to 601W 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 SP750 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 very good as we see a value of 88.95% and the exhaust temperature is 61C.
Load Testing Summary
The Lian Li SP750 did a very good job in our initial load testing. When we look at the voltage regulation, we see that the SP750 had peak changes of 0.09v 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 by absolute numbers very good. Now, in a relative sense, this unit did slightly trail the SilverStone Sx750 but it was just on the 12v rail.
When it came to efficiency, this unit posted a range of 87.92% to 90.38% efficient at 120v AC input and 85.90% to 89.72% efficient at 100v AC input. These values are decent overall and seem like they would be in the rough range for an 80 Plus Gold power supply. Lastly, the exhaust temperature peaked at 54C at 120v AC input, 59C 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.