Base Retina iMac Fan ALWAYS On

AirCanada22

macrumors newbie
Original poster
Jan 5, 2015
16
0
Hi all,

Just picked up my Retina iMac not even a week ago, and apart from one small thing I'm completely in love with it....that one thing would be the fan noise. When I first took it out of the box and started playing around with it, it was dead silent. But the very next day, and every day since, the fans have been running, audibly, even at idle. I can close every program or start the thing up from hours of being off and the fans still kick in instantly. I do a lot of writing in a silent room so this is both noticeable and bothersome.

Is this something I have to live with or can I expect an update or software adjustment to fix this?

Thanks!
 

dasx

macrumors 65816
Jun 18, 2012
1,098
17
Barcelona
Right now it is fluctuating between 90-94% idle, and the fans are still on.
Yeah, there's definitely something wrong. Fans are OK though, they're doing their job, because a retina iMac being at 95% the whole time will get warm.

The problem is you've got something that is taking power away from you. Consider installing OSX in a pendrive/hard drive (a USB 3.0 or you'll die) and boot from it, then install all your software again 1 by 1 and see which one causes the problem.

EDIT: ooops, 94% idle you mean the CPU usage is just at 6%? I misunderstood!! Sorry.
 

Alesc

macrumors 6502
Nov 11, 2014
253
11
France
Right now it is fluctuating between 90-94% idle, and the fans are still on.
The fan is always on on an iMac, and it's OK to hear it a little ;)
If you are worrying about that, you can try to install Macs Fan control or iStat menus and see that the fan is correctly spinning at default speed on idle: 1200 tpm.
 

andy9l

macrumors 68000
Aug 31, 2009
1,697
364
England, UK
If you are worrying about that, you can try to install Macs Fan control or iStat menus and see that the fan is correctly spinning at default speed on idle: 1200 tpm.
This. This is all you need to do to work out if you have a problem. If your iMac is idling at over 1,200rpm, you've got a problem.
 

kucyk

macrumors regular
Sep 24, 2007
100
9
Something is sucking up the CPU power, next time when it happens open up the activity monitor and see what process is harming your CPU
 

phpmaven

macrumors 68040
Jun 12, 2009
3,403
466
San Clemente, CA USA
The fan is always on on an iMac, and it's OK to hear it a little ;)
If you are worrying about that, you can try to install Macs Fan control or iStat menus and see that the fan is correctly spinning at default speed on idle: 1200 tpm.
It's not normal to be able to hear it all the time, unless the OP has bionic ears. If you can hear the fan 24/7, then something is wrong.
 

Alesc

macrumors 6502
Nov 11, 2014
253
11
France
It's not normal to be able to hear it all the time, unless the OP has bionic ears. If you can hear the fan 24/7, then something is wrong.
In a very silent room, I can hear the soft whisper of my very silent late 2013 iMac fan, and I'm far from being Superman (I have a permanent and continuous tinnitus since I'm 12).
 

cynics

macrumors G4
Jan 8, 2012
11,554
1,873
In a very silent room, I can hear the soft whisper of my very silent late 2013 iMac fan, and I'm far from being Superman (I have a permanent and continuous tinnitus since I'm 12).

I can also hear an imac in a silent room but from what the OP is describing its not an idle fan speed since it was quiet the first day then noticeably louder ever since.

We won't know until he/she installs an program that reports fan speed.
 

AirCanada22

macrumors newbie
Original poster
Jan 5, 2015
16
0
Thanks for the help, everyone, and sorry for the confusion in my wording: CPU usage was approximately 10% --> 90% was idle.

I installed a monitoring program. Fan speed is hovering around 1200 RPM and CPU/GPU temperatures are both ~30 degrees Celcius.

I take it this means that this level of noise is normal and that there's nothing I can do about it?
 

cynics

macrumors G4
Jan 8, 2012
11,554
1,873
Thanks for the help, everyone, and sorry for the confusion in my wording: CPU usage was approximately 10% --> 90% was idle.

I installed a monitoring program. Fan speed is hovering around 1200 RPM and CPU/GPU temperatures are both ~30 degrees Celcius.

I take it this means that this level of noise is normal and that there's nothing I can do about it?
Its impossible for us to say without hearing it. At 1200rpm I can hear my iMac but I need to listen for it, virtually any other noise is louder.

The software is reporting 1200 rpm which doesn't make it 1200 rpm. Also we don't know if there is something wrong with the fan itself.

Any accurate comparisons you can make with the sound of fan compared to other things that have the same volume when operating?
 

MacSignal

macrumors regular
May 8, 2010
241
1
FWIW, my experience is about the same after coming from a couple of retina laptops that were dead silent at idle. From the first boot with the iMac, I immediately noticed noise where there was none before. iStat reports a fan speed of about 1200 RPM. The computer seems to be operating without any issues.

I am not suffering too much, but it was a little disappointing and surprising that the iMac does not meet the same standard as the last two retina laptops I had. Maybe next iMac revision...maybe not.

This iMac happens to have a Fusion drive, so I began to wonder if what I am hearing might be spinning drive platters as much as the fan. Wish I could compare to one with a SSD to know for certain.

Whatever it is, there is a distinct difference in noise on vs. off that I did not notice with the last two retina laptops that I had. All IME. YMMV. Like the OP, I frequently work alone in a quiet room, where noise differences would be more obvious.

What I am hearing is something you would never hear this in the din of an Apple store, with TV or music playing, and probably not even with another person in the room working on another computer.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,425
780
Thanks for the help, everyone, and sorry for the confusion in my wording: CPU usage was approximately 10% --> 90% was idle.

I installed a monitoring program. Fan speed is hovering around 1200 RPM and CPU/GPU temperatures are both ~30 degrees Celcius.

I take it this means that this level of noise is normal and that there's nothing I can do about it?
Yes, that's quite normal.
 

SmallDane

macrumors member
Dec 23, 2014
99
17
Denmark
A brand new iMac with fans running at the lowest possible speed (1200 rpm) should be near silent. If not, there is something wrong with it. Could something be blocking the air intake or exhaust? Can you describe what kind of noise you are hearing?
 

Nismo73

macrumors 6502a
Jan 4, 2013
885
481
FWIW, my experience is about the same after coming from a couple of retina laptops that were dead silent at idle. From the first boot with the iMac, I immediately noticed noise where there was none before. iStat reports a fan speed of about 1200 RPM. The computer seems to be operating without any issues.

I am not suffering too much, but it was a little disappointing and surprising that the iMac does not meet the same standard as the last two retina laptops I had. Maybe next iMac revision...maybe not.

This iMac happens to have a Fusion drive, so I began to wonder if what I am hearing might be spinning drive platters as much as the fan. Wish I could compare to one with a SSD to know for certain.

Whatever it is, there is a distinct difference in noise on vs. off that I did not notice with the last two retina laptops that I had. All IME. YMMV. Like the OP, I frequently work alone in a quiet room, where noise differences would be more obvious.

What I am hearing is something you would never hear this in the din of an Apple store, with TV or music playing, and probably not even with another person in the room working on another computer.
It's normal. Retina MacBook, pretty much have to put your ear to the keyboard to hear it. IMac, it's normal to hear it at normal sitting distance in a silent room. The iMac doesn't have the fan design on the MacBook, so right there it has a strike against it in the amount of noise it produces.
 

phpmaven

macrumors 68040
Jun 12, 2009
3,403
466
San Clemente, CA USA
In a very silent room, I can hear the soft whisper of my very silent late 2013 iMac fan, and I'm far from being Superman (I have a permanent and continuous tinnitus since I'm 12).
OK, if I put my ear within a few inches of the bottom of iMac, I can just barely hear the fans. But at normal distance, I can't hear them at all. And I have pretty good hearing.

Anyway, the bottom line is, if your iMac is making enough fan noise to be bothersome at normal operating times, then there's something wrong, period. It should be whisper quite, practically silent.
 

AirCanada22

macrumors newbie
Original poster
Jan 5, 2015
16
0
hi all, thanks for the replies.

The sound is a low whir, exactly as you'd expect a healthy fan to sound, but it's audible at total idle and 1200RPM. Considering I do a ton of writing and reading on my machines, and keep a silent room for those purposes, this is somewhat upsetting.

I also don't understand why it was dead silent on day 1 and has since never calmed down. I'm going to call Apple about this. It's not enough to make me want to return the machine, but it doesn't seem so unreasonable that at total rest the machine be quiet. My 11-inch MBA with 2GB of RAM only ever got this loud under huge stress (VLC + 10 chrome tabs). To think that this machine at idle is as loud as the MBA under stress is upsetting.
 

WilliamG

macrumors G3
Mar 29, 2008
9,090
2,549
Seattle
hi all, thanks for the replies.

The sound is a low whir, exactly as you'd expect a healthy fan to sound, but it's audible at total idle and 1200RPM. Considering I do a ton of writing and reading on my machines, and keep a silent room for those purposes, this is somewhat upsetting.

I also don't understand why it was dead silent on day 1 and has since never calmed down. I'm going to call Apple about this. It's not enough to make me want to return the machine, but it doesn't seem so unreasonable that at total rest the machine be quiet. My 11-inch MBA with 2GB of RAM only ever got this loud under huge stress (VLC + 10 chrome tabs). To think that this machine at idle is as loud as the MBA under stress is upsetting.
1200rpm is the "resting" speed. Not sure why you're thinking it's as noisy as an MBA. My wife has an MBA and under stress it's like a small vacuum cleaner it's so noisy. Either your fan is broken or.. I have no idea. But 1200rpm is normal.
 

AirCanada22

macrumors newbie
Original poster
Jan 5, 2015
16
0
I'm comparing the sound of my Retina iMac "at rest" to the sound of my MBA when the fan first kicks in. I don't think this is "whisper" quiet; maybe there's something wrong with the fan or maybe it's just meant to run loud, but if another iMac Retina owner can say that they have to strain to hear the fan than there is something wrong with mine.
 

redheeler

macrumors 604
Oct 17, 2014
7,659
7,484
hi all, thanks for the replies.

The sound is a low whir, exactly as you'd expect a healthy fan to sound, but it's audible at total idle and 1200RPM. Considering I do a ton of writing and reading on my machines, and keep a silent room for those purposes, this is somewhat upsetting.

I also don't understand why it was dead silent on day 1 and has since never calmed down. I'm going to call Apple about this. It's not enough to make me want to return the machine, but it doesn't seem so unreasonable that at total rest the machine be quiet. My 11-inch MBA with 2GB of RAM only ever got this loud under huge stress (VLC + 10 chrome tabs). To think that this machine at idle is as loud as the MBA under stress is upsetting.
The noise my iMac makes when idling at 1200rpm is barley audible and not even close to the loudness of an external HDD, or central heating system for that matter. It certainly isn't as loud as my 13" rMBP under stress, which as WilliamG said sounds like a small vacuum cleaner.
 

phpmaven

macrumors 68040
Jun 12, 2009
3,403
466
San Clemente, CA USA
I'm comparing the sound of my Retina iMac "at rest" to the sound of my MBA when the fan first kicks in. I don't think this is "whisper" quiet; maybe there's something wrong with the fan or maybe it's just meant to run loud, but if another iMac Retina owner can say that they have to strain to hear the fan than there is something wrong with mine.
If it's not "whisper" quiet, then something is definitely wrong, especially as it seems the fan is running at 1200 rpm. That's the speed mine is running at and I literally have to put my ear within a few inches of the bottom of the screen to hear it.
 
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