Hard drive noise in 2011 iMac

[RobNor]

How noisy are they?

 

[Icy1007]

As noisy as any other 7200RPM Hard Drive.

 

[stigzy]

By seeing technical specs on apple.com it says:

"Sound pressure level (operator position): 18 dBA at idle"

http://www.apple.com/no/imac/specs.html

 

[Dresevski]

Mine is silent unless it is booting or I manually put the fanspeed up.

 

[ShiftyGray]

Mine is silent unless it is booting or I manually put the fanspeed up.

I can hear mine rumble each time I do something, such as open an app or switch to the next song in iTunes.