Question about be quiet! Pure Rock 2

Hello fan + processor freaks I have mounted this Pure Rock 2 FAN on an Intel Core i7 4770K / 3.5 GHz processor. The mainboard is an Asus MAXIMUS VI FORMULA (SOCKET 1150). I mounted everything as it was in the manual. Now I got a CPU fan error message for the first time when I switched it on. Before that, there was a CPU fan of a cooling unit on it. So I press F1 and look in the Bios. The CPU FAN is visible there and the fan speed is also displayed. After that, the message no longer came up. But every time I start Windows 10, this CPU Fan Error message comes up again and again. Is it possible that the be quiet! Pure Rock 2 fan has too little rpm? Should I ignore the message? The average temperature is 41 degrees according to Speccy and also went up to approx. 60 degrees, at operating load. Does anyone have an idea how I should proceed? Thank you very much!