CM_USA

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Feb 22, 2012
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612 comes with two fans running at 600-2000 rpm
612s comes with one fan in which maximizes at 1300rpm. Also comes with an adapter to lower the speed to 900rpm to be more silent.
 

CM_USA

Honorable
Feb 22, 2012
141
0
10,710
Looking at the specs, the 612 will push more air than the 612s. It all depends on placements of the cpu coolers' fans. As long as the fans is blowing the air towards the exhaust fan at the rear of the case your system should have no problems.