SilverStone Element ST50EF-Plus is a decent mainstream 500 W power supply that can really deliver its labeled power at 50º C, providing a decent efficiency between 82.8% and 83.7% if you pull between 200 W and 300 W from it. At full load, however, efficiency was below 80%. It is very important to remind that our tests are tougher than the ones promoted by the 80 Plus organization, which test power supplies at a room temperature of only 23º C, a temperature impossible to be achieved inside a typical PC. Since efficiency drops with temperature and we pulled 500 W at more than double the temperature used by 80 Plus our result was lower than the one provided by this institution. In our opinion our results are more realistic.

The main positive voltages were really within 3% from their nominal values, as promised by the manufacturer. Translation: voltages were closer to their nominal values than required under ATX specification, which is great.

Ripple and noise levels were always below the maximum allowed.

In summary, you won’t have any problems when using this unit.

It exploded while we overload it (at 590 W), but you have to keep in mind that this is an extreme situation that obviously show not be attempted. Of course we prefer when a protection from the power supply kicks in preventing this kind of thing from happening.