Scythe Stealth Semi-Fanless Power Supply
 

The rear portion of the Scythe Stealth Semi-Fanless Power Supply has all the
standard features found on most PSU units but incorporates a large black
coloured aluminum heatsink for passive cooling and an 8-position rheostat knob
which controls Scythe's Flexible Fan Control System (FFCS). The FFCS is a
unique system that provides six different temperature configuration modes as
well as the ability to adjust fan RPM levels.

It look a lot like the silentmaxx models. Perhaps it is made from the same manufacture.