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I have an iMac 27" i7 late 2009. I just replaced the internal Seagate 1Tb hard disk with a seagate barracuda 3Tb (compatible temperature sensor). Everything is working fine except for a very irritating low frequency hum from the hard disk. I tried already many things like tightening the hard disk screws (it makes the problem worse) and placing the iMac on a soft rubber pad. Is there something I could do to dampen or mitigate the hard disk noise?
Just a thought, but you may consider loosing the screws? ( making sure they have a tiny bit of blue threadlocker of course, if not already on there), they dont need to be that tight…… in fact in my standard regular non mac PCs i only use two screws. Also they are some silicone grommet solutions to reduce vibration, i have not done this for an imac, but thought it might give you an idea of a product to look for. lastly, check for anything too tight, or loose that may cause it during the taking apart and putting it back together. If possible having the computer on while u track down the source of the noise. just some thoughts, again i have not taken this approach for your specific computer.
SUPER!!! TY !!! Added some rubber (bicycle tire repair kit) and the humming sound from 7200rpm HD is gone!
