I am going to test two rather specific power supplies in this review. Despite being high-wattage units, these products from SilverStone and Seasonic have no fans and rely on convection for their cooling, which makes them absolutely silent.
Click the following link for a description of our testing methodology and equipment and a brief explanation of what the specified and tested parameters of power supplies mean: X-bit Labs Presents: Power Supply Units Testing Methodology In-Depth. If you feel overwhelmed with the numbers and terms this review abounds in, refer to that article.
You can also go to our Cases/PSU section to check out reviews of all other PSU models we have tested in our labs.
We will mark the actual power consumption of three system configurations (discussed in our article PC Power Consumption: How Many Watts Do We Need?) in the cross-load diagrams. This will help you see if the tested PSU can meet the requirements of a real-life PC.
SilverStone Nightjar SST-ST45NF
First goes the 450-watt unit from SilverStone. Although the Nightjar series has been produced for a second year already, Silverstone doesn’t yet offer an alternative. That’s understandable because fanless PSUs are very specific products and their developers focus on achieving high efficiency and use reliable and durable components. Such PSUs have a long lifecycle as the consequence.
The Nightjar series also includes a 300W (SST-ST30NF) and a 400W (SST-ST40NF) model.
The PSU comes in a black-and-gray box on which its absolute noiselessness is indicated.
The Nightjar SST-ST45NF has the typical appearance of a fanless PSU: a meshed case with a massive aluminum heatsink as the top panel. The heatsink has a lot of low fins, so it is best cooled by a rather slow stream of air, for example from a system case fan. Theoretically, fanless PSUs can work with no active cooling at all, but you should have at least one low-speed fan inside your computer to make life easier for your PSU, mainboard and hard disks.
Besides the heatsink, the bottom panel is blank, too. It is blank because there is the printed circuit board behind it which would block the airflow anyway. Moreover, the PCB has dangerous voltages up to 400 volts.
There are two LED indicators next to the power connector: one signals that the PSU is working and another, that the PSU is not overheat (the indicator changes its color to red in case of overheat). I guess this is a useful thing. The green color will calm down many users who have no experience with fanless PSUs and do not know what temperature should be considered safe.