be quiet Power Zone 2 1200W Power Supply Review
Power Efficiency and Voltage Ripple
Voltage Ripple and Efficiency Testing
When reviewing new power supplies at OC3D, we use our dedicated SunMoon PSU Tester, one of the most expensive (if not the most expensive) tools in the company’s arsenal. Here, we can see exactly how well a unit functions. We look at both a PSU’s efficiency and power stability. To do this, we utilise bespoke PSU testing equipment to give us an in-depth look at each power supply’s performance. This kind of data collection is impossible when using a PSU with standard PC components.
Power Efficiency
As an 80+ and Cybenetics Platinum-rated PSU, we knew that its power efficiency should be good. The be quiet Power Zone 2 1200W did not disappoint. At 100% loads, this PSU was 92.5% efficient, and at 50% loads, the PSU was 94% efficient. Great results.
Voltage Ripple
Voltage ripple is often overlooked by consumers. It is best described as the stability of specific voltages that the PSU delivers. A PSU with bad ripple will see voltages vary a lot more. In extreme cases, this can damage components or shorten their lifespans. Voltage ripple stability is one of the many reasons to choose a high-quality power supply. That means buying from a reputable brand and avoiding anything that isn’t 80+ certified.
An important thing to note here is that none of the PSUs in this graph are “bad.” Even units with the highest ripple in our charts, like the original Corsair RM1000 (from 2014), are usable within your system without any issues. We used this specific power supply within one of our main workstations for years and had no trouble with it. As we said before, only extreme levels of voltage ripple are dangerous. Regardless, we feel that these results are important, as we do not want to see PSU manufacturers moving backwards with this metric. We do not want to see the return of PSUs with high levels of voltage ripple.
There’s no other way of putting this. Compared with the other PSUs on this chart, the voltage ripple on the Straight Power 2 is on the high side. That said, voltage ripple remains fairly low at low-mid power loads. Additionally, ripple remains below 30 mV at all times. Yes, there are better PSUs with regard to voltage ripple, but this level of ripple is good enough for almost all consumer use cases. It’s worth noting that the ATX standard permits a maximum peak-to-peak voltage ripple of 120 mV on the 12V rail. This PSU sits well below that standard.
