The 90mm fan installs via two fan clips and has built-in rubber bushings to act as silencers when clipped to the heatsink. The assembly was fairly easy, although I should note that you must be careful not to bend the aluminum fins while installing the fan as it is easy to do. It would be nice if the heatsink could accept two fans for a push/pull configuration.
Taking a closer look at the cooler itself we see the three 8mm all-copper heatpipes are exposed at the base of the cooler for direct contact with the processor's integrated heat spreader. The pre-installed AM2/AM3 clip is held on by two screws on the base of the unit. The surface of the bottom face of the cooler is not a mirror polish but has a milled texture. I see this in many stock coolers, and is not a surface I approve of. I have always found that a flat, mirror-like surface is best for transferring heat. There are also noticeable gaps between the copper heatpipes and the aluminum base which must be filled with thermal grease before mounting or else air may be trapped between your cooler and the processor which can be detrimental to your ability to wick heat away from the CPU.