Despite being based on an identical design, it appears that the slightly lowered capacity of the Silentnight 500W power supply improves the electrical efficiency across its nominal loading range. Thus, the Silentnight easily honors its 80Plus Platinum certification, with the efficiency peaking up to the whooping 94.2% under nominal load.
As the Silentnight 500W unit has no fan, the only temperature we could viably record is that on the surface of the aluminum bottom of the power supply. Note that these results are not directly comparable to those taken from any typical power supply with active cooling! The temperatures were within our expectations, with the chassis barely getting warm while the power supply operates. However, remember that most of this heat will be released within the case, not forced outside it by a cooling fan.