Visual inspection
The Be Quiet! Dark Rock Slim is a cooler designed to offer a good clearance around the CPU socket. The heatsink uses a total of 50 aluminum fins and has a thickness of just 72mm and a height of 159mm. The fan that equips the Dark Rock Slim is a variant of the 120mm Silent Wings 3 model.
The dimensions of the cooler with the fan installed are: 159 mm x 152 mm x 72 mm.
The heatsink has a single tower design and uses a total of 50 aluminum fins and four heatpipes. The top plate of the cooler is thicker than the cooling fins and has a linear brushed texture with black anodized paint applied. At the center, a reflective Be Quiet! logo is placed into the surface of the top plate, creating a black and white contrast. 
The Dark Rock Slim has four nickel-plate copper heatipes, each with an outer diameter of 6mm. The heatpipes are arranged into the classic U shape, to provide the best possible heat transfer. The heatpipes are making contact with both the baseplate of the cooler and with a smaller heatsink found above.
The base of the cooler is made from the same type of nickel-plated copper as the four heatpipes. The surface of the base is smooth and has a circular pattern etched into it, a result of the manufacturing process.
The front side of the heatsink uses two rubber strips as the contact point for the 120mm fan. These rubber strips are found with other Be Quiet! air CPU coolers, as it is a simple and effective way of dampening vibration and having a good base for the fan to sit on.
The Dark Rock Slim has a single 120mm fan which is a variant of the standard Silent Wings 3 series fans. The fan has the model number BQ SIW3-12025-LF-PWM, and has a minimum speed of 500 RPM and a maximum speed of 1500 RPM.
The cable of the fan is shorter than usual, it is long enough to reach all fan headers located around the socket, but too short to be used as a case fan. In addition, the cable is covered by high quality sleeving and has a 4 Pin connector for power.
