The fan in that PSU is a Yate Loon D12SH-12 (120 mm, 12 V, 0.3 A, Sleeve Bearing
If you intend to replce it, then I suggest you open it up, measure the fan casing. Height, width and length should be the same as they are notmally square. Also take a photo and post it. Check if the fan is a PWM...