Seasonic Platinum Series Fanless 460W Power Supply Review

A Detailed Look

The Seasonic Platinum Series Fanless 460W power supply features a black matte finish and measures 160mm (6.3”) deep. Instead of a fan the enclosure features large, open honeycomb vents on the top, sides and back to allow for natural convection cooling. The front and bottom panels also have smaller vent openings.

Note: just because the X-460 PSU doesn't have a fan does not mean that it doesn't need adequate airflow to dissipate heat.  Ideally, existing case fans should generate a flow of air around and/or through the PSU for cooling.  If you plan to install the X-460 fanless PSU in a case that doesn't have any case fans then it will need to have plenty of open area around the PSU with an opening above to let the hot air out.  Convection cooling relies on being able to draw cool air in through the back and sides with an unrestricted path for hot air to flow out the top.

The Platinum-460 Fanless power supply is fully modular and has a good assortment of cables/connectors.  All of the cables are a flat, ribbon-style cable except for the main 24-pin ATX power cable, which is covered with a black, braided plastic mesh sleeving.

Connectors:

• (1) Main power connector (24-pin/20-pin) 600mm
• (1) ATX12V/EPS12V (4-pin + 4-pin) 650mm
• (2) PCI Express (6+2-pin) 600mm
• (5) Peripheral Optical/HDD (4-pin)
• (6) Peripheral Serial ATA (15-pin)
• (1) Peripheral FDD (4-pin) adapter

The new Seasonic Platinum Series Fanless power supplies are based on the X-Series design.  One of the most obvious features is the +3.3V and +5V voltage regulators have been moved off of the main PCB (or daughter cards) and onto the modular DC connector board, which mounts to the front of the enclosure.  This is a major innovation shared by all X-Series power supplies and offers several advantages.

• Reduced wiring results in less resistance to current flow and higher efficiency
• Reduced wiring also results in a cleaner layout with better airflow
• Reduced part count results in higher reliability and lower cost

(Courtesy of Seasonic)

The biggest advantage to moving the two VRMs onto the DC connector board is that it virtually eliminates the high current distribution wiring that previously had to route the +3.3V and +5V outputs to the connector panel.  This distribution wiring had to carry high currents and therefore was subject to line resistance and voltage losses.  With the new design, only +12V has to be delivered to the modular DC connector board, which can be distributed more efficiently with fewer and smaller wires (as voltage goes up, current goes down for the same power).     

The Platinum-460 Fanless main PCB is basically a +12V PSU that also includes a small -12V regulator and the +5VSB section.  All of these output voltages are sent out via modular connectors soldered directly onto the front of the main PCB.  Additional connectors supply all the other connectors directly from sockets soldered onto the modular DC connector board.

Looking inside the PSU, you will see a single Japanese made primary capacitor rated for 270uF, 420V, and 105°C.  The secondary features predominantly solid polymer capacitors with a few Nippon Chemi-Con electrolytic caps thrown in for good measure.  Just like all previous X-Series power supplies we have seen, the layout and component selection appears to be excellent.