Efficiency
With 82.1% efficiency in our test, the PSU easily makes the 80+ range. While it is not a spectacular result it is well in the bulk there with other PSUs from well-known manufacturers. Cooler Master claims 88.14% efficiency in their testing, our testing definitely does not reflect that. Since we are testing at only one specific load, there may be other load scenarios where the efficiency is higher.
Fan Noise
While not being silent the Cooler Master UCP 900W is definitely one of the quieter PSUs tested so far.