Fan noise on iMac after new Solid State Hard Drive installed....normal??

Question

Level 1

0 points

Fan noise on iMac after new Solid State Hard Drive installed....normal??

Recently had to have a new Solid State, SATA Hard Drive installed............and now, after the computer sits unattended, you can hear what appears to be fan noise, and can also feel air exiting from the top of the computer. Once I'm using the computer the noise subsides by 50% or less.

I never noticed or heard the fan noise prior to the installation of the Hard Drive.

Any thoughts or suggestions would be greatly appreciated.

iMac (21.5-inch Mid 2011), OS X Mavericks (10.9.5)

Posted on Aug 22, 2015 1:55 PM

Reply

Answer 1

Kappy

Level 10

361,741 points

Aug 22, 2015 2:13 PM in response to wendol05

The computer has three fans that run continuously. Mostly they are quiet unless the computer is overheating. The vent is at the top of the computer.

Runaway applications can shorten battery runtime, affect performance, and increase heat and fan acti…

Mavericks and later

Open Activity Monitor in the Utilities folder. Select All Processes from the View menu. Click on the CPU tab in the toolbar. Click twice on the %CPU column header to display in descending order. If you find a process using a large amount of %CPU, then select the process and click on the Quit icon in the toolbar. Click on the Force Quit button to kill the process. See if that helps. Be sure to note the name of the runaway process so you can track down the cause of the problem.

Reply

Answer 2

wendol05 Author

Level 1

0 points

Aug 22, 2015 2:35 PM in response to Kappy

Thanks for the response.

I checked the Activity Monitor.........and it's running at about 97% idle.

Crazy thing is, the fans run when the computer is unattended, with the screen black/blank.

Reply

Answer 3

Kappy

Level 10

361,741 points

Aug 22, 2015 2:42 PM in response to wendol05

You want to check what is outlined in my last paragraph above. Look for anything using up a lot of %CPU as shown in the list. Something should not be running when the computer is idle unless Spotlight is re-indexing the HDD or you have some other process that only runs when the computer is idle such as a backup, for example.

Reply

Answer 4

markwmsn

Level 6

15,023 points

Aug 22, 2015 3:36 PM in response to wendol05

The iMac may be responding to a missing or misconnected temperature sensor on the new drive. Not sure why the fan would get quieter when you used the computer, though. (Might be misconnected in such a way as to invert the reported temperature. Sounds farfetched, but I've seen reports suggesting that Apple may have changed the circuitry in that way at some point along the progression of iMac models.)

Reply