Not great, especially in any OC'd system - that fan will be responsible for singlehandedly dragging air in, shoving it across the CPU and then back out again (not counting the PSU fan, you shouldn't rely on that for system cooling anyway!). And one noisy fan is much worse on the ears than any number of quiet ones! Much better idea is to set all fans to minimal settings (if they are variable-speed) - at low speeds most fans are virtually silent, if not then they're probably on their last legs! One of the (few) uses of a multi-fan controller is to change fan speed (via power control) of otherwise static single-speed fans.