With this 120mm SlipStream fan you can take advantage of the PWN Function on your mainboard, which is offered by the latest boards with a 4-pin CPU cooler fan header, as opposed to the traditional 3-pin CPU cooler headers, which did not allow for the mainboard to vary the spin speed of the connected fans. With the new 4-pin PWN fans and coolers, the included PWN Function will control the fans spin speed and noise output depending on system temperatures and required cooling performance on the fly. This 120mm SlipStream PWM fan offers 0 ~ 1300RPM for 0 ~ 26.5dBA & the maximum achievable airflow is 74.25CFM at the full 1300RPM. For best operations, combine this chassis fan with a 4-pin fan header PWN Function supporting mainboard, however the package also includes a 4-pin peripheral connector adapter, so you can connect this fan directly to your PSU (note this will prevent the PWN Function from operating and the fan will run at maximum RPM continuously). This fan is 120mm x 120mm x 25mm, weighs 117g and has an MTBF of 30,000hours.