One of the other things that make the SLK-900U unique is that you can mount just about any type of fan on it, from a 70mm to 92mm. The “stock” fan that ThermalRight suggests is a Delta 92mm fan that moves an impressive 110.18CFM at a noisy 55dBA. However, most vendors on the web sell the unit without a fan so you can pick and choose which one suits your needs. For this review we will be using a ThermalTake Smart Case Fan-2 80mm fan which at full speed runs at 4800RPM, 48dBA, and moves 75.7CFM.