In early August we reviewed the Corsair AX1200i, the first power supply for high-end desktop PCs to use a digital controller, and gave it the Gold Award. It proved to be extremely efficient, very silent with very low ripple values, plus you can control the PSU entirely via Corsair link. Finally we saw some innovation in the world of computer power supplies.
Since then Corsair released lower-capacity models built with the same technology. Hardware.Info tested the 760-watt AX760i and 860-watt AX860i.
Traditional power supplies have analogue components for regulating the voltages in order to keep the efficiency as high as possible. Corsair is the first to implement a DSP (digital signal processor) in a desktop PC power supply. Corsairs claims a DSP is faster and more accurate, which should results in extremely low ripple values. The manufacturer promises ripple values less than a third of the maximum ATX specifications (40 mVtt instead of 120 mVtt).
ATX specs also indicate that voltages can deviate by a maximum of 5 percent, but Corsair has lowered that to 1.5 percent. Stable voltages makes a PC run more stable as well. The faster and more accurate working of the DSP along with the absence of various analogue components also lower the amount of energy consumed by the PSU itself. The AX1200i is 80 Plus Platinum certified, but Corsair claims that the power supply is more efficient than (almost) any existing 80 Plus Platinum models. We will put that claim to the test.