27" iMac hard drive noise

I purchased my iMac in december last year and the noise of the fans drove me crazy. I finally found a solution which is kindof techno but now I at least have a nice iMac that I can enjoy in silence.
The thing is to slow down the harddisk fan rotation speed. You can do that by using a program called smcFanControl to set the maximum speed of the fan. The GUI of smcFanControl doesn't allow you to do that, you'll have to do it in a terminal window.
In a terminal window do the following:

/Applications/Utilities/smcFanControl.app/Contents/Resources/smc -k F1Mx -w 2af8

For example, this will set the maximum RPM of the HDD fan to 2750.

The -k parameter is the HDD fan for the iMac. The -w writes the value of the RPM which is the hexadecimal representation of 4 times the RPM (i.e, 4 x 2750 = 11000 which is 2af8 in hex representation). Don't ask me why, but that's how it works.

Now, enjoy the silence.

Hi Suzkid,

I recently got my new iMac 27" i7 2.93Ghz and the HDD was making noise too. (Very annoying i must say for such unit!) Is it normal you ask? Well no! Really depends on the HDD quality and age....

What i did is I took it back to Apple store and they where kind enough to replace it with another one, since I did that same day I got it. Then I could not verify the same problem in the store because of the noise there but when I plugged it in home it was running really smooth wit no noise... (big difference from the previous unit I had!).

I really think this is HDD issue, and does that means that it will cause problems.. well no, but just that clicking noise is annoying... it does sounds like old HDD about to go bad... And my recommendation is that you work this out with Apple...

I just bought from the Apple On-Line store this week a 27" i5 Quad-Core 1GB Video iMac Refurbished (saved $ 300) and it arrived flawless/dead quiet. Looks like new as well.

I got Vmware Fusion 3.1 running on it running WinXp, Win Vista & Win 7 (besides adjusing to how to learn how OS X works, so I am taxing the HD a lot and still dead quiet.

I have had my 2009 iMac i7 2.8 27" for 2 months now. Exactly every 60 seconds I hear 3 clicking sounds from the lower left of the machine. Like others, the sound can be ignored if you have other entertainment running like a tv or music. However, if it is quite and you are really trying to concentrate on a project it becomes quite annoying. I really like the machine and the functionality but the clicks are driving me crazy.

I am a little reluctant to take the unit back due to most of the responses here,if the drive goes dead I'll take it in. I wish Apple would address this issue with a firmware update since it obviously impacts quite a few users.

hi kkellogg,

The hard drive is not located on the lower left side of the iMac, but it is located in the middle top side of the iMac 4inches or so under the iSight camera in your case the only thing that can make sense for the noise coming from there is the cooling fan. Ether way should not make noise again this is new unit so you should have Apple take a look at it.

Goran

Thanks Goran!
The 3 distinct clicks are indeed coming from the lower left. If I place my ear under the fan, the noise is very clear and since it happens exactly every 60 seconds something must be sending a signal to perhaps trigger the fan. I will take your advice and have an Apple dealer look at the machine.

Hi guys,
my story is a little bit of bitter fun, I got my iMac 27 inch i5, 3 weeks ago and it all started with the sound coming from the hard drive..... So i read a little about it and next day i booked an appointment with the store and they replaced it for me .... So I brought the iMac back home (despite me going to apple store with that big thing which is hard and costly) .
But... the sound was there this time even louder, the replacement had WD. i thought its no big deal maybe and i tried to stand it, after a few days it got louder and more annoying . I contacted apple care again This time they said they will send someone to pick it up (a company called AMSYS), long story short they came and took my imac, instead of replacing they repaired it, but my mac was less than 3 weeks old . anyhow i received the imac today and when i powered it on again the computer was really really SLOW, i decided to install the OS X on it again so it might get better and it did, and this is exactly where i found that the sound is not gone and its even worse (it's Seagate now) also i found that my optical drive is clicking SO loud and its like it cant read. i contacted apple care again this evening and they said they would log it and someone from apple MIGHT contact me and they can set up another repair.To hear the sound of my hard drive there is a test on youtube http://www.youtube.com/watch?v=4icnH4V5zgA just listen 😟 .
i hope that someone would care a little bit, i think its apple's concern to check the product before shipping and if not so at least provide good spare parts,

Same issue here. Have the offending Seagate (ST31000528AS), bought from Amazon last week (Jan '11) VERY annoying sound. I can understand a little bit of noise when writing to the drive, but I bought a computer, not a POPCORN MAKER. More than a little irritating.

From what I've read so far, sounds like it could be fixed w/ a firmware update. Hope this happens. I can't decide weather to just wait it out and get a fan in the room (doesn't take much white noise to drown it out completely), return to Amazon, or go to the (relatively) nearby Apple store.

Sigh.

HD specs below.. Serial number (QP1020ZKDB6 ) says this machine was put together in week 2 of what I can only assume was 2011 (did they make this machine w/ these specs in week two of 2010 . . . . If so, maybe I should head to the Apple store and try to get a newer machine. . . . .?)




Hardware:

Serial-ATA:

Intel 5 Series Chipset:

Vendor: Intel
Product: 5 Series Chipset
Link Speed: 3 Gigabit
Negotiated Link Speed: 3 Gigabit
Description: AHCI Version 1.30 Supported

ST31000528AS:

Capacity: 1 TB (1,000,204,886,016 bytes)
Model: ST31000528AS
Revision: AP25
Serial Number: 9VPAVLBJ
Native Command Queuing: Yes
Queue Depth: 32
Removable Media: No
Detachable Drive: No
BSD Name: disk0
Rotational Rate: 7200
Medium Type: Rotational
Partition Map Type: GPT (GUID Partition Table)
S.M.A.R.T. status: Verified
Volumes:
Capacity: 209.7 MB (209,715,200 bytes)
Writable: Yes
BSD Name: disk0s1
g&j imac:
Capacity: 999.86 GB (999,860,912,128 bytes)
Available: 868.01 GB (868,005,965,824 bytes)
Writable: Yes
File System: Journaled HFS+
BSD Name: disk0s2
Mount Point: /

Well I'm going into the Apple Store Saturday to have them look at it (yay AppleCare). Disk Utility says the HD is fine but SMART Utility (which I downloaded from the Apple site via its software page) says it's failing.

So rather than wait for it to completely fail (and have to listen to the constant krrr krrr krrr) I'm gonna nip it into the bud and have the HDD replaced.

Hi BOFHMAN!

I am trying to follow your steps, but I have a few questions?

1: first how can I know what type(wd, hitachy, SG, etc) of hard disck is inside my mac i5 ? To see if this procedure will work..
2, when I get into http://www.nu2.nu/pebuilder/ i see a lot of links to download stuff but I dont see the PE BOOT CD one...which is the right one?
3 how can I make sure that I am using FAT32 or NTFS

thanks mate!

I just upgraded the RAM on my 27", iMac, i7, 2tb Hitachi, and saw no speed improvement. I thought the noise was unique to my machine but clearly not. Mine also slows right down when the noise is happening and is quite frankly annoying!!

Hi Everybody,

Same story over here:
Bought mine in December 2010. Noticed the sound from day one. Tried to live with it but eventually took it back to the Apple Store here in Oakridge Mall in Vancouver. Guy who helped me put his ear against the back and told me he couldn't hear anything weird. Told him that there was a lot of noise around us and that I sit and work in a less noisy environment. He suggested to set the 'Put Hard Disk to Sleep" to NO. Tried that. No effect.
Took it back for a second time. They kept it for a full day and ran different HD diagnostics on it. One test they ran 4 times the lady which helped me told me. HDD is fine, no issues.
But the HDD is driving me crazy... same sounds as I hear you guys talk about.

I'm thinking of calling them on Monday and tell them that there are 24 pages on the Apple Discussion board and that the only solution I've read so far is replacing it with a 2TB HDD.

Any other suggestions?
Anybody really successful with BOFHMAN's solutions. Scares the **** out of me to take that step.

Take care,

Roland

I've put this in response to Ali O's smc code post in another thread, but thought i'd put it in here too to see if i can get any more help on it, cheers

Hi, Ali,

i tried copying your "/Applications/Utilities/smcFanControl.app/Contents/Resources/smc -k F1Mx -w 2af8" code into terminal, but i get a reply saying that
"-bash: /Applications/Utilities/smcFanControl.app/Contents/Resources/smc: No such file or directory"

is copying the code above into terminal the right thing to do or am i doing it wrong? i have the latest version of smc (2.2.2)

I have a 27 inch quad core imac with a 2Tb Hitachi drive, had it from brand new since late october and noticed from the very start that after being switched on and booted up, the hard disk fan will start reasonably slow and quiet and gradually get faster and louder, 15 minutes will pass and the hard disc fan is running at 5000 rpm and is pretty loud, even though only running safari! Temperatures look ok at about 35 - 40 C all the time. the fan will run at 5000rpm until the imac is put to sleep or rebooted, when booted back up again, the process starts over again.

its always been pretty annoying but thought that was just something to do with having a quad core, but after reading up on it and seeing that it should be running fairly silently unless really stressing it, i know something isnt right.

anyone with any experience of this and getting it fixed in the UK? really cant have it sent to apple for them to poke at it for a few weeks, mainly because i cant afford the time without it with final year uni work deadlines looming, and the sheer heft of the thing getting it to a shop without a car. Really dont want to just get it swapped either as loading back all my applications and work will probably take longer than actually just getting the thing fixed!

cheers for any replies.

P.S
it seems to be just the hard drive fan running very loud and fast, not the hard drive "stomach grumble" that many are reporting.

Apple, if you watching.. just DO something with this hard drive noise...
As I say before:
1. it's annoying.
2. This clicks not healthy to the disk.. (that's what the Seagate tech support told me).

Webberdrum:

I have an 3.06 Intel Core 2 Duo. What you describe in your third paragraph is exactly what happened with mine. The HD, HD fan, HD cable was changed by Apple repair contractor at my home but still had the problem. In fact the HD fan also ran up to about 5000rpm in my case. Took it to Apple and was told it was a cable and had to wait for it. After 3-4 days and being told it was a cable when I received it back, the work order on the machine said the logic board was changed. That was a little over a month ago and everything is O.K so far. You may have the same problem and eventually the logic board may have to be changed. There is software that can modulate fan RPM-I think-but that is not curing the problem. If you haven't, get the extended warranty and then, somehow, cart the thing to an Apple store because I have no idea how long it will last. But, continually back up your work to an external drive or one day you will find you have lost all of your school work.