Building a quiet PC? These modular PSUs don't have any fans

(Image credit: Seasonic)

Seasonic is expanding its range of fanless power supply units (PSUs), which previously consisted of a solitary 600-watt model. There are now three more wattage options to choose from: 700W, 500W, and 450W.

All four fall under Seasonic's Prime Fanless TX family. Somewhat surprisingly, each one is also either 80 Plus Platinum or Titanium certified. Those are the two highest certifications available, the others being Gold, Silver, Bronze, and just regular 80 Plus (in descending order).

Boutique builder Velocity Micro has a pretty good primer on the 80 Plus certification program that is worth a read. In short, these certifications denote levels of efficiency, which in turn relates to how much (or how little) energy gets wasted as heat.

"A power supply’s job is to convert the AC power from your wall outlet to DC power that your other components can use. The efficiency rating is simply the power outputted to those components divided by the wattage drawn from the wall socket. So then a 500W power supply with a 50 percent efficiency rating would draw 1000W to get to that peak output. In this example, the other 500W are wasted as heat in that conversion process. How efficient a power supply is also depends on the percentage of the rated load being outputted, with most PSUs running at maximum efficiency around 50 percent load, or 250W in this example," Velocity Micro explains.

Getting back to Seasonic's new fanless models, the highest wattage model (700W) is 80 Plus Titanium certified. That means it's at least 94 percent efficient at a 100 percent load. By comparison, the 80 Plus Bronze certification requires 82 percent efficiency at full bore. It's pretty impressive that Seasonic's models can maintain ultra-high efficiency levels without any active cooling.

(Image credit: Seasonic)

Credit goes to Fanlesstech for noticing these new models, which have been added to Seasonic's website. All four PSUs are fully modular. The 700W and 600W models both sport a single 24-pin main power connector, two EPS 12V connectors, four 8-pin/6-pin PCIe connectors, 10 SATA connectors, five 4-pin peripheral connectors, and a single molex-to-SATA adapter.

The 500W and 450W models cut the number of 8-pin/6-pin PCIe connectors in half (so two), and have eight SATA connectors instead of 10.

Pricing has not yet been announced. As a point of reference, the 600W model debuted at $190, which is expensive. The 500W and 450W models should cost less. All four are backed by a lengthy 12-year warranty.

Paul Lilly

Paul has been playing PC games and raking his knuckles on computer hardware since the Commodore 64. He does not have any tattoos, but thinks it would be cool to get one that reads LOAD"*",8,1. In his off time, he rides motorcycles and wrestles alligators (only one of those is true).

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