Seasonic are using a high grade Hong Hua fan (Model: HA1225M12F-Z). Seasonic use these family of fans in many of their power supplies currently available. This is a Fluid Dynamic bearing model offering long life and quiet operation. It is rated 0.45A 12V @ 2050RPM.
Below - a High Resolution Gallery of the internal layout of the Power supply.
Soldering quality throughout is excellent as we would expect from a high quality brand such as Seasonic.
We can see that the new Focus units are using a double layered PCB on the modular daughter-card and they have removed in line capacitors on the cables. Due to the high efficiency Seasonic don't need to overpopulate the PCB with many heatsinks.
This design is a full bridge topology on the primary side along with an LLC resonant converter. On the secondary side FET's installed on the PCB's solder side rectify the +12V rail. Minor rails are generated through a couple of DC-DC converters.
Seasonic are using high grade Japanese capacitors throughout the build with a single 105c rated Nippon Chemi Con positioned in the primary stage from their KMR series. This is rated 400v 470uF. In the secondary stage Seasonic have adopted a range of solid and standard electrolytic from Nippon Chemi Con.