The Cougar CMX 700 W can really deliver its labeled power at high temperatures, providing high efficiency between 83.6% and 86.0% when we pulled between 140 W and 560 W. At 700 W, efficiency dropped to 80.6%, which is below the 82% minimum required for the 80 Plus Bronze certification. As we always explain, the 80 Plus certification tests are conducted at a room temperature of only 23° C, while we test power supplies above 45° C, and efficiency drops with temperature. Ripple and noise levels were always very low.
The main problem with this power supply is voltage regulation. Starting at 560 W, voltages got outside their allowed range, what can make your computer behave erratically. We tested two samples, and both presented the same problem. Therefore, we can’t recommend this unit.