27" iMac humming noise

[Stingray454]

I've got 2 27" iMacs at home, any both have worked very nicely since I got them (even though they have the slight yellow tinge, but it's so faint I've decided to live with it). I got them in November, and they are well used since both are used for working from home at least 8h / day.

Yesterday I noticed one of them emitting a humming noise. It sounds like some kind of resonance sound from the harddrive or similar. It fades from silent to a noticeable humming and back again with an interval of about 5 seconds. I've heard similar sounds before when harddrives or CD players have not been tightly secured and starts resonating inside the chassis - that said, I'm not certain that is the problem, it's just an educated guess.

The question is - what can I do about this? Is this something apple would consider a warranty issue? Do i void my warranty if I open it up and look for any loose screws? Or is this a sign that the harddrive is about to fail?

 

[Yakuza]

From what i've heard, many people have changed the desk or just put a cloth or mouse pad under the iMac, sounds kinda silly but i guess it worked for them

 

[mdewberry]

Check out this thread on the previous page:

Happy with my i7 Imac, but droning noise...

I describe in detail what I found with this noise.. I attributed mine to a hard drive fan... Are the symptoms I describe what are happening with you?

 

[dborja]

From what i've heard, many people have changed the desk or just put a cloth or mouse pad under the iMac, sounds kinda silly but i guess it worked for them

+1
Probably resonance between your iMac and desk surface.

 

[chsfnn]

droning noise

My iMac 27" i5 is having the exact same intermittant droning noise. I'm thinking of returning it and waiting until all the bugs for this model have been worked out. After paying so much for this model, the idea of using a cloth to solve the problem just doesn't jive with me!

 

[eelpout]

When I read threads like these I sometimes think people forget this is a machine with moving parts. People have bought too much into Steve J's view that an iMac is an appliance to be admired.

on the other hand I use to work with a guy years ago who ran a lengthy SCSI cable from an old Mac II to a closet so he wouldn't have to hear the hard drive. so there ya go.

 

[aneftp]

My core i7 which I've had for 2 weeks was super quiet UNTIL last night when I was doing CPU intensive programs.

I was running Handbrake, youtube flash video, and Photoshop at the same time.

The CPU was running at 65%, which I couldn't believe with the core i7 (probably flash consuming all the cpu cycles).

Anyways, I started hearing the same humming noise. I felt the back of the iMac. Considerable heat coming from the back of the iMac on the opposite side of the optical drive. It appeared hot. So the sound is probably the fan running.

No big deal. My screen is just about perfect.

I've had loud PC towers in the past and believe me, this humming noise is no where near as loud as the older PC towers.

Now compared to my 24 inch imac core2 2.4 I previous had, the core i7 is much louder. The 24 inch imac core 2 was super quiet.

 

[TMRaven]

You can download iStat menus to keep a track on your cpu load, component temperatures, fan speeds and more at all times. Usually when I run cpu intensive apps like handbrake, iStat menus shows my cpu to heat up, and the fans to start kicking in.

I can believe the i7 having 65% of its capacity used by handbrake though. Hell, when I use handbrake to encode my videos in high profile x264, iSat menus shows all 8 of my logical cores being maxed out.