[dche5390]

I bought a second hand 24" iMac from an OCAU member. Recieved it yesterday and after a few dramas with my TM backup (screwed up and did a fresh install instead), it is all good, EXCEPT...

The iMac makes this irritating humming noise.

Am I correct in assuming this is the internal HDD (500G of unknown brand and speed) making the noise? It certainly doesn't sound like any fan that I've heard.

Before I did a fresh install, it would make a pulsing humming noise. Now, its just a steady hum which is much less irritating on my brain and bowels. I'd still like to find the source of the humming noise.

FYI, its a 2007 model, 2.8GHz "extreme" with that HD2600 Pro as a video card.

Damn the screen is enormous. Not recommended for a 13" 1280x800 user to suddenly jump back to 1920x1200 (or vice versa). Its like having "Hi, I'm a Mac" screamed right in front of your face.

[leon]

Mine never made a humming noise. These machines shipped with WD branded drives.
How loud is the humming? Is it like an optical drive spinning (just to get a reference) or is it quieter than that?

[Huy]

I think it is supposed to make a quiet humming noise. At least, my iMac makes a similar 'hum' when it is on.

Mine is a 2007 iMac (2.4) with WD 500GB BTO.

[gehenna]

My older white one made a humming noise when i would dim the brightness. No noise at full brightness, progressively louder noise as i lowered it. This was a 2006 model though i think

[dche5390]

Originally Posted by leon

Mine never made a humming noise. These machines shipped with WD branded drives.
How loud is the humming? Is it like an optical drive spinning (just to get a reference) or is it quieter than that?

Not as loud and distracting as an optical drive spinning. Its hard to describe. Its not "loud" per se. It has a low frequency humming noise. Its akin to a lightbulb emmiting a humming noise?

Originally Posted by Huy

I think it is supposed to make a quiet humming noise. At least, my iMac makes a similar 'hum' when it is on.

Mine is a 2007 iMac (2.4) with WD 500GB BTO.

I had the same iMac as you did a year ago. I do remember a very quiet humming noise but not to the extend as the one I have now. Its not loud but irritatingly soft?

Originally Posted by gehenna

My older white one made a humming noise when i would dim the brightness. No noise at full brightness, progressively louder noise as i lowered it. This was a 2006 model though i think

No difference in noise level regardless of screen brightness.

[leon]

Maybe it is the LCD inverter making the noise?

[reemixx]

Mine doesn't make a noise, at least not like what you described. There's a very faint hum if you put your ear right next to it, but that's completely normal computer noise and not audible from a distance greater than 30cm in a regular (as in not completely silent) environment.

For a little while, it made a faint high-pitched whistling noise, but that seems to have stopped now. Mine is also the 2007 model, but the 2.4GHz version, also with 2600 Pro vid card.

Perhaps it would be a good idea to contact the person you bought it from and ask if it was also making the noise for them.

[ParisHilton]

Could be a capacitor.

[iJohn]

Yeah mine makes a really lite hum but its hardly noticeable. You gotta be virtually quite with nothing on to hear it.

Don't have any issues going to sleep with it on doesn't keep me awake like the old days of a PC with that power supply fan spining

[dche5390]

Originally Posted by iJohn

Yeah mine makes a really lite hum but its hardly noticeable. You gotta be virtually quite with nothing on to hear it.

Don't have any issues going to sleep with it on doesn't keep me awake like the old days of a PC with that power supply fan spining

Its only noticable when using it. Otherwise, in bed, the noise in inaudible, unlike the yumcha PSU's I used to install in my cheap beige yumcha case but with $1000 worth of parts inside.

I'll just have to live with it. Until I get sick of it and pawn it off and get a brand new one

[BoxDog]

Vaguely (ok, really) OT but the capacitor comment above reminds me - has anybody ever heard their iPhone making a high pitched screeching noise while charging? Just asking.

[iJohn]

boxdog that's a negative bout the iPhone while charging man

[dche5390]

It doesn't appear to be the screen. When I sleep the display, the humming noise persists.