imac 2011 27" power supply problems

[mohammad.golche]

i have an imac 2011 27" , imac PSU was making the electrical buzzing noise.
i replaced it with another PSU .

now imac is silent but cpu fan is running at max rpm speed (4200).

i checked HWMonitor temperatures and PSU temperature was 130 c , but PSU is not hot.

please help me...
where is problem ? how can i solve it ?

 

[barbu]

Seems like a sensor is missing somewhere, so it fails safe and runs the fans. If you are certain the temps are ok, you can override the fans with SMC Fan Control to quiet things down.