A:Answer The rear fan is 92mm. I replaced mine with a Noctua 92mm fan that is much less noisy and worth the upgrade just for the silence. Otherwise, there's (just barely) enough room at the top of the case to add a 120mm fan and I've seen others add a 92mm to the top in closer to the IO shield. For extra cooling, I would seriously consider an AIO unit. My CPU runs incredibly cool no matter what I throw at it now.
