Fan Speed increased after upgrading hard drive on iMac 2011

[Ataa]

iMac 2011 was working well and fine until I updated its hard drive last week. Seem like I did a huge mistake with this update. After I updated the hard drive I found that the hard drive fan revolves to the full speed without me doing anything. However I am happy that the update didn’t harmed anything else other than the hard drive fan. Now, I am not asking any such complicated question or suggestion just wanted to have some kind of hardware based solution that could help me to control my hard drive fan. I know that SMCFanControl could be one of the best solutions for controlling the fans but I guess you all know that it is software and I need not want any kind of software so better do not suggest me with such software as a suggestion. Hope you all got my requirement, now it’s up to you how you guide me and help me out of this trouble.

[chuck28]

This issue has now become too common and also increasing tremendously. I do have a 17 iMac, there was a main HD already existing into the system. So therefore believing that even I might get into such trouble I simply replaced this inbuilt hard drive with another newly bought SSD. Luckily until now I haven’t found or encountered any sort of trouble with the with the temperature sensor and hoping that the I wont face it in future too. Recently I learned that whatever iMac desktops coming up right now have no sensor attached with their internal hard drives. Might be they are keeping the sensor but at some other location that is being unidentified.

If you really believe in “Precaution is better than cure” then I think you should follow my steps and do replace your main hard drive with some other SSD which is a better option. Not just I am not facing any problem but also I am getting a better performance, currently my fan is running better at 1090RPM.

[Yistor]

Yeah that’s a better option I feel. Installing a new SSD would do a better job and also will increase the life line of both your system and drives. Even I have implemented the same trick into my iMac 2011. Just because I was facing this trouble I simply replaced my hard drive with a brand new OCZ vertex 2 (hope you know that this is one of the best SSD that you could ever get). Swapping my existing old drive with this 3.5 inch SSD proved as a better option for me. People are lucky enough if they are able to get their fan revolution issue solved with just swapping the drive. But there are cases where users do replace their hard drive and end up getting no positive results, so if you are planning to go for this swapping option it would be much better that you do it under your own risk, either your fan would mess up more with the drive or else get down to the normal condition. Anyways mainly I would like to tell you that if surely you want to go for a new SSD better prefer OCZ Vertex 2, nothing is better than this.

[Vicky Woodley]

The only thing I can say is iMac 2011 is worse than 2010 version. I have iMac 2011 with me facing the same temperature and fan revs issue. I went through everything and inspected my machine all the way, while detaching the inner hard drive I found that there was no such hard drive temperature probe connected within the system. Now I personally suspect the Seagate HDD custom firmware but when i tell this to my friends they doubt and do not agree with my opinion. I am now willing to connect the drive to another Sata port believing that there might be some issue with the main Sata port connection itself. That would sound funny but sometimes it happens that we suspect major thing but the main issue lies within some unexpected minor part. There could be chances that the data regarding the temperature is being passed and transferred through directly through the data cable.

Also I believe that because of the different firmware in some other format now days apple is trying to get a smart temperature information through the Sata port. As far as I know there’s only enterprise SSD that comes up with only one a temperature sensor where as the normal SSD doesn’t shows up such thing.

[Mayoor]

Got the exactly similar issue with my iMac, my iMac is brand new. I bought it with the best configuration. Now what I did was simply replaced and swapped the already existing original Western Digital Caviar Black with 120GB intel 510 series (even this is brand new). What happened during the installation was, I noticed a kind of noise in-between the installation but then I realized that this noise was due to some kind of incomplete installation. Later on after completing the installation when my Time Machine was migration I found that the same noise was being noticed by me, in fact the noise went high this time. Believing that there might be something wrong with the installed hard drive fan I simply checked the speed of the fan and found that the fan was actually running at 4000 rpms. Long back I learn that sometimes such issues occur due to the faulty or lack of driver update, so therefore I decided to install the latest update for the driver but then after getting the latest update I found that the fan condition was getting too bad. The speed kept on increasing going beyond 5000 rpms. I hope you must be aware that as much as the speed of the fan increases the corresponding sound increases along side and this is what happened in my case. Now the condition is that I am not even able to listen music or watch movie on my system as the noise disturbs a lot.

After a month of struggling I found that the fan speed actually went out of the control and I wasn’t able to get it to the normal speed. And I also came to know that once if I manage to get the fan speed under control I will get the entire problem resolved automatically one after the other.

For controlling the fan the only best solution is to go for fan controller software and when it comes to such software SMCfancontrol is the only one that comes to the mind. And currently this is what I have installed into my system and I must say its working with an ease. No other software is better than this one. And if in case instead of software if you prefer any hardware solution then a new SSD is the only solution left. And if buying a new SSD is fine for you then I think you should go for nothing other than OCZ Vertex SSD, they are the best one present in the market.