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sewer bear · Sep 19, 2006, 07:50 AM

This is my first post - and first Mac computer - so please bear with me if this is common knowledge of something! I purchased the 17" iMac back in June while there were still only 2 available models (that I know of, at least - i.e. before the 24"). Anyways, my problem comes when the computer is plugged in but turned off : that's not in any sort of sleep or hibernated mode. There is an extremely high-pitched noise that comes from the back of the monitor/computer. It's not very loud, but I try to turn the unit off at night - and it drives me crazy when there is no other sound in the room! I've asked a couple people, and not everyone can hear it it seems (I have pretty sensitive ears). After it is on or in hibernate, etc. there appears to be no more high-pitched sound.

Anyways, I'd like to turn it off at night sometimes to save energy if nothing else. Has anyone else experienced this problem with this or any other iMac models? If so, is it a common thing or should I be concerned? Should I just leave the power on all the time? I've owned two other computers - both PCs, most recently an HP laptop (the doorstop, as I call it) - an neither did this to my knowledge. Please help if you can! Thanks!

Parky · Sep 19, 2006, 10:13 AM

Turn the power off at the wall outlet as well, or remove the plug from the socket.
It is probably the transformer in the iMac emitting the noise, as it is still powered.

Ian

P · Sep 19, 2006, 11:42 AM

IME, this happens in some cases if the computer is not connected to a grounded outlet - at least my old iMac G3 does that. If possible, try to connect it to a grounded outlet.

quiklee · Sep 19, 2006, 12:48 PM

whoa . . sounds like a crazy problem . . . let us know when you find the solution . . . honestly, I'd take it back to the Apple store and have them look at it . . .

sewer bear · Sep 19, 2006, 02:29 PM

Hmm, doesn't sound like many people have experienced this problem...that's not good...

It is in fact connected to a grounded power strip. But I've tried it with and without, and it doesn't seem to make a difference.

And, yes, I could unplug it every time I power down, but I was trying to avoid moving my computer and crawling around behind my desk every night.

I would just take it back to the store, but I ordered it online, and the closest Apple store is about an hour and a half away...but I may end up having to do just that. I haven't tried Apple's telephone tech support yet, but that will probably be my next step. Hum...

P · Sep 19, 2006, 03:45 PM

Yeah, take it back to the store. While it most likely isn't anything serious, there is an elevated risk of the power supply frying completely. If you want to avoid the issue in the meantime, plug it into a powerstrip with a powerswitch and use that to turn it off - or pull the plug from the back of the iMac. That last is what I did when my iMac G3 started doing that way back. I wouldn't call it that high-pitched, though - everyone could hear it. The iMac was far out warranty so I didn't do anything more, and the noise went away eventually. The G3 still runs, but it's not the main machine anymore.