I just got my Denon this week. I also put two 120mm fans on top to pull the hot air out to create the pull/push effect inside the unit. I can’t believe how much $20 fans help cool my receiver. One guy said for every 10 degrees we cool the receivers, we increase 70% of the life of the Denons. That’s worth the money I spent in fans in spades. I bought my Denon AVR-X4200W about 6 years or so ago for my 4 Ohm 5.2 (later 5.2) setup but I bought fans a year or two later. Still works! I don't have any animals that can clog intakes, though, and the ambient temperature is a balmy 20C +-3, except when it's real hot like above 25C :D