Quality wise, both the Tachyon 550W and the Silentnight 500W units were significantly better than our initial expectations. Advanced users and enthusiasts will be pleased by the overall quality of both power supplies, which may be visually simplistic but they are built using some of the finest components available. Rosewill did well by trusting Super Flower to be the company behind their high end products; it is no coincidence that both of these power supplies are retailing with a 5 year long warranty.
The electrical performance of both units is excellent. Both units are capable of voltage regulation better than 2%, a pleasing figure, while the ripple suppression is better than most units of similar specifications that we have ever tested. However, the efficiency of the Silentnight is notably better and more stable than that of the Tachyon; perhaps something to be expected from a passive power supply but the Tachyon fails to meet its 80Plus Platinum certification, even if only by a borderline margin, which is a little disappointing even if the overall efficiency of the power supply is very high nonetheless.
As far as differences are concerned, beyond the obvious fact that one unit is a fanless design and the other is a typical power supply, it is rather strange that the Silentnight 500W unit appears more capable than the 550W version of the Tachyon, delivering better performance and even having two more PCI-E connectors. We believe that the Silentnight is significantly underrated, most likely because of its fanless design. Remember that the Silentnight only comes in a 500W version, while the Tachyon line of power supplies reaches up to 1000W.
Rosewill's prime focus is value and the Tachyon 550W is no exception. Their appearance may be simplistic and their bundles Spartan, yet the Tachyon 550W unit can be found retailing for about 75 USD, an amazing deal for an 80Plus Platinum modular power supply. Unfortunately, we cannot say the same for the Silentnight, the retail price of which is more than twice as high, at about 160 USD. It is a fully silent, passively cooled product, yet the price difference alone will definitely drive most users towards the "common" Tachyon.
|Rosewill Tachyon 550W|
|Rosewill Silentnight 500W|