The E6300's stock hsf is actually very extremely quiet if run with Smart Fan settings, when not overclocked. Whereas when you overclock, it's not advisable to keep Smart Fan settings on. Disabling it keeps your fan spinning at full speed, which my motherboard reads at 1800-2000rpm, which is a lot slower than other stock hsf. Even at that kind of speed, I'd say the noise isn't loud which I'm surprised. This stock HSF fan actually helped me achieve very high overclocking numbers.