Hah, that was going to be my suggestion.
Fans only get noisy when they're dusty.
I know, I know (we did this in another thread) but I didn't want to shut it down at the time. Unplugging the fan didn't seem to make any difference to mobo temp but I don't actually know where that sensor is in relation to the northbridge, hence the 'do I need Northbridge cooling' question.
I had to shut it down yesterday for something so took the time to clean all the fan blades.
I have noticed the rear case fan is stop/starting so I reckon that needs replacing.
I know, I know (we did this in another thread) but I didn't want to shut it down at the time. Unplugging the fan didn't seem to make any difference to mobo temp but I don't actually know where that sensor is in relation to the northbridge, hence the 'do I need Northbridge cooling' question.
I had to shut it down yesterday for something so took the time to clean all the fan blades.
I have noticed the rear case fan is stop/starting so I reckon that needs replacing.