New iMac Fan Noise

Is it coming from the bottom left of the machine?

I've had various iMacs and there are 3 different noises with ssd models

1) mechanical fan clicking / rattling noise - constant rattle once the machine gets hot enough. Cannot be replicated with fan control software and doesn't go

2) crackling from the bottom left of the screen. Occasional crackling / clicking usually with dark screens and at low brightness 1-4 bars. Goes with higher brightness around 5 bars or higher.

3) ticking from anywhere around the screen. Usually goes after a few weeks. It is due to the glue on the tape settling down.

 

Marc,

Please 2-3 SMC resets, if these do not cure the issue then immediately call AppleCare, a new iMac should be silent. This will be covered by the warranty, if the machine is less than 14 days old and you bought it directly from Apple they you can return it for any reason for an exchange or refund. If not you have 90 days of free AppleCare telephone support and a 1 year warranty. Why you would go to a rumor site for tech support when you have all that coverage available is puzzling. If yo don't know how to do the SMC reset please click

https://discussions.apple.com/docs/DOC-3603

for instructions.

 

Im currently on my second iMac, the second one has just come and still has the noise

 

that noise is the fan rattling issue i experienced. Exactly the same noise i had on 2 2013 iMacs. I had 2 other 2013 iMacs which didn't do that noise but they did crackle intermittently at low brightness from the bottom left of the display. I kept a crackling one and keep the brightness up. I couldn't live with that fan noise.

You may hear it from the bottom at there are vents or more obviously on the rear.

According to the teardown and this image : http://cdn.mactrast.com/wp-content/uploads/2012/12/27-inch-iMac-teardown.jpg - the fan is just above the exhaust vents.