Our load tests utilize a couple of FAST ATE active load testers and a variety of other equipment such as an oscilloscope, power conditioner, temperature probe and a power consumption meter. You can read more about our standard testing approach here.
The tests performed are based around six conceivable setups that are out there and progressively load down the PSU up to the power supply's limits or 1000W, whichever comes first. Since our test equipment's limits are higher than that of the Seasonic Platinum 520 Fanless 520W power supply, we can test it to the maximum.
The above tests represent typical loads that we have measured from various systems and are meant to give a rough idea of where your computer might fall in line with our tests. Please keep in mind that each system is different and actual loads can vary greatly even with similar hardware.
Let's start by taking a look at the voltages to see how well this unit did during testing. Starting with the 12V rail, we see 1% regulation from start to finish with a total drop of .05V. The 5V rail managed to stay within 1% of specification with a total drop of .02V from start to finish. Moving towards the 3.3V rail, we see that regulation was within 1% of specification with a total voltage drop of .04V.
DC Output quality for the Power Force 850W was excellent and well within specification. During Test 1, we saw 18mV of noise on our scope. When we increased the loads in Test 2, the ripple climbed to 26mV at a little over half load. During Test 3 under a load of 520W, the oscilloscope showed a maximum of 35mv on noise on the 12V rail.
Seasonic Platinum 520 Fanless is rated for 80 PLUS Platinum efficiency. This means that the power supply must perform at 90%/92%/89% efficiency at 20%/50%/100% loads respectively. As you can see, the Platinum 520 Fanless passed on our bench, and wasn't close to failing at any point.
Once again we have another Seasonic unit that is nearly flawless on our test bench. Looking at the power supply from a performance standpoint, it is perfect. Voltage regulation is kept at an impeccable 1% across the board while DC output quality is amazing as well. The Platinum 520 Fanless also performs with Platinum rated efficiency as advertised.
None of this is an industry first. We've seen 1% regulation with a handful of units in the past and we've also seen extremely low ripple on the 12V rail, too. Platinum efficiency isn't anything special either, as we've seen it from just about everyone in both actively and passively cooled variants. What is special and an industry first is that it is all wrapped up in a single package all while being cheaper than most other fanless power supplies of similar wattage. It is very clear that the Platinum 520 Fanless represents the pinnacle of everything that Seasonic has been able to achieve in over 30 years of R&D.
If you're in the market for a fanless unit, you'll be doing yourself a disservice by not strongly considering the Seasonic Platinum 520 Fanless 520W power supply above the competition.