Overclockers Club published a review on the Phanteks PH-F140 (XP, SP, SP_LED) Case Fan
A quote from the article:
Based on the specifications given by Phanteks, the fans seemed to be just as awesome as they were said to be. The idles and the loads both were very impressive across the board and all @4.4Ghz. Even with the XP using the QSA adapter the temperatures were all so far down I wouldn't even be afraid to up the voltage and the clock speed for a faster overclock. Oddly enough, the XP actually performed worse than its brethren at the 1200 rpm speeds and was still defeated ever so slightly by the Noctua at its 1500 rpm setting (which is faster and a bit louder than the Phanteks XP). I think a slightly faster PWM range would have easily matched the slightly more brutish Noctua. All of the Phanteks handled this overclock without breaking a sweat.Phanteks PH-F140 (XP, SP, SP_LED) Case Fan Review @ OCC