CPU fans on 2010 iMac 100% after SSD install

Discussion in 'iMac' started by lazmeister, Sep 27, 2011.

  1. lazmeister, Sep 27, 2011
    Last edited: Sep 27, 2011

    lazmeister macrumors newbie

    Joined:
    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #1
    So here is my situation and story. I have a late 2010 iMac 27" i5, I decided to buy the 128gb M4 Crucial SSD to install as a secondary drive. I bought the whole harness and wiring kit off Ebay for it with the SATA cable, replacement power cable and the plastic holder for the SSD. So I used this tutorial http://www.twam.info/hardware/apple/installing-additional-ssd-in-mid-2010-27-imac#comment-3102 for helping in installing it. I did remove about everything (power,LCD backlight board,superdrive,airport, and the logic board. After taking it apart about 6-7 times and realizing I needed to put the power in first to the 1TB then the SSD, the drives showed up. In the middle of all of this, I accidentally pulled the LCD off the case without realizing the LCD Backlight sync cable was still plugged in. I almost ripped off the connector the board. So I tried to re-tape the connector in and prayed it would work, luckily the display is still fine. I actually ordered a replacement board, just in case to make sure it won't fail on me. So after the whole install and now knowing the iMac interior like the back of my hand, my CPU fan is going crazy at 100% and showing 0rpm on my OS when i install any fan reading software. I double checked the CPU fan (lower left of the front of the iMac) cable to make sure there wasn't any loose cables from the 4 that connect in the connector, I checked every cable to make sure they are plugged in. I've read numerous installs on forums around the internet and some people have this issue after install an additional SSD, but no answers as to why its happening. I don't know who to go to for support so I'm hoping someone on here can give me some ideas.

    BTW the SSD is blazing fast! I have all my applications and OS on the SSD and home folder on the 1TB, still crazy fast for PS and anything else I throw at it.


    Update: I've tried using SMCFanControl to see if I can modify the fan speeds, HDD and ODD look fine (900-1500rpms) and CPU showing 0rpm. I'm thinking my SMC is shot! (I've tried PRAM and SMC reset but to no avail)

    I also tried putting everything back to factory (cables and all) and the CPU still ran at full speed telling me something went wrong.
     
  2. Daud macrumors regular

    Joined:
    Oct 23, 2008
    #2
    Sorry, I have no advice for you. But can you share your opinion whether after your experience, you would go for the OWC install instead ?
    I am getting a 2010 i7 2.93 (open box) for $1200 and am inclined to have OWC do the upgrade, rationalizing that with that price, I can afford it instead of doing some harm to the iMac.
     
  3. panzer06 macrumors 68030

    panzer06

    Joined:
    Sep 23, 2006
    Location:
    Kilrath
    #3
    Try this:

    http://www.hddfancontrol.com/

    I use it on my 2010 i7 that was upgraded to 2TB. It has an hour free demo so you can see if that fixes it. If it does, you buy it and problem solved.

    It fixed my OS X fan issue. Windows 7 must use smart for the temps because I have not had a fan issue when booted to Windows 7.

    Cheers
     
  4. lazmeister thread starter macrumors newbie

    Joined:
    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #4
    You actually don't have to take everything apart. Some people out there were using just y-splitters, but I prefer the whole wiring harness and kit. It's not that hard to do if you follow those instructions and go very very slow and take your time with unplugging and plugging things back in. I will reply on here once I get the inverter board to see if that replacement will fix the CPU fan. Nice deal BTW on that iMac!

    ----------

    Hi Panzer, I unfortunately purchased this software only to find out my HDD fan is fine, this software ONLY controls your HDD fan and not your Optical or CPU fan as SMCfancontrol does for FREE. Don't waste your money people! but yeah my HDD fan is actually running fine at around 1300-1500 rpms
     
  5. panzer06, Sep 27, 2011
    Last edited: Sep 27, 2011

    panzer06 macrumors 68030

    panzer06

    Joined:
    Sep 23, 2006
    Location:
    Kilrath
    #5
    That is unfortunate. I didn't even see CPU, just SSD & fan. Ah indeed the brain is a mystery. Best of luck.

    Cheers,
     
  6. accessoriesguy macrumors 6502a

    Joined:
    Jul 8, 2011
    #6
    from what i remember, the new iMacs have temperature sensors on the HDD (idk why they added this) originally it was believed that without a proper hard drive (one with a temperature sensor) your mac would not work and Apple makes more money with exclusive hard drives.

    Luckly this is not the case, however when you install a non temperature censored hard drive the fans will default to 100% speed.

    So don't worry this is normal occurrence, but you may want to try to control the fan somehow i believe there are apps, but I don't know much else. Hope this helped with your mystery.

    Here's a helpful discussion on apple's discussion forum
    https://discussions.apple.com/thread/2017647?start=0&tstart=0

    Free Mac Help provided by Cellularfactory.com
     
  7. Spike88 macrumors 6502a

    Joined:
    Jan 25, 2010
    #7
    I too heard http://www.hddfancontrol.com/ is a good program to install / configure when replacing with non-Apple HDDs / SSDs. Install it and try it. If it controls the HDD fan speed, then buy it. That's what I'd do - instead of re-opening the case - trying to find that special heat sensor (that doesn't exist on the non-Apple drive).
     
  8. lazmeister thread starter macrumors newbie

    Joined:
    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #8
    Maybe you guys are confused, as I posted that I installed an additional SSD and left the existing HDD plugged in. I've read numerous installs from forums and users that did this have had no issues at all, the users that installed a Replacement HDD of their existing one had issues with HDD fans and such.

    Here are my fans stats:

    ODD: 997pm
    HDD: 1700rpm
    CPU: 0rpm (almost like the fan may be going but its only a 9 month old computer)

    Temps:
    HDD: 40
    CPU: 36
    Ambient: 15
    GPU Diode: 60
    GPU Heatsink: 56
    Mem Controller: 43
    Optical Drive: 46
    Power Supply: 37

    All seem normal to me, no reason for the CPU fan to be running at full speed, but give no feedback to the SMC as its reading 0rpm even though the fan is literally running like a jet engine!
     
  9. Frederiksberg macrumors member

    Joined:
    Feb 24, 2010
    Location:
    Frederiksberg
    #9
    Well, it seems like there might be different posibillities here. Maybe you forgot to plug the CPU-sensor back in?
    Another possibility is, that you damaged the censor. I did something like that, when I took mine apart. Had to change the whole motherboard.
     
  10. lazmeister thread starter macrumors newbie

    Joined:
    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #10
    The CPU sensor is fine, as you can tell it is reading the CPU temp as normal. It's the fans communication with the SMC that I'm worried about, seems like there is a connection problem, but the fan is still spinning so its getting power.
     
  11. Smacky macrumors 6502

    Joined:
    Jul 23, 2008
    #11
    Sounds like a damaged RPM sensor on the CPU fan. Might have been shorted out or something when you were working on it
     
  12. JInx3110, Sep 28, 2011
    Last edited: Sep 28, 2011

    JInx3110 macrumors newbie

    Joined:
    Sep 16, 2011
    Location:
    N.Ireland
    #12
    i was reading an article recently i'll try to find it and give a link or quotes but basically this company had taken apart the 21" new iMac (2011) and discovered that as soon as you move the hdd and or SSD out of the bay the fan speed jumps to 100% and the AHT (apple hardware test) is FAILED. Something to do with Bios loaded in the stock HDD to control the fan

    perhaps ur problem is similar in concept, apple most likely don't want people performing upgrades (when they make so much money on aftersales upgrades) so they pretty much booby trap the machine so they can tell if even a hdd or ssd upgrade has been performed outside of apple stores

    Cheeky bar stewards. I hate the way apple are becoming more and more restrictive as they get more popular. (thunderbolt port will not accept MDP source to restrict external display usage to other apple products only) for example

    I know this info doesn't help and i don't want to waste your time but it might give someone with more expertise (such as urself) an idea on how the problem can be remedied
     
  13. lazmeister thread starter macrumors newbie

    Joined:
    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #13
    Interesting, I might agree with you but would that not just be the HDD fan? From every forum/post I've read (I've read dozens) with SSD installs, its the HDD fan that people are having issues with and not the other fans. One thing I worry is that the CPU fan is actually giving no feedback to the operating system. Its a possibility though with what you are saying, once I get the LCD Backlight board I will install it and put everything back to factory. I wonder if AHT will come back with a HD error or if the CPU fan will still be acting up. Who knows, I will definitely have to report back once I do this.
     
  14. fhall1 macrumors 68040

    fhall1

    Joined:
    Dec 18, 2007
    Location:
    (Central) NY State of mind
    #14
    Put it back together to factory delivered status, then take it to Apple and tell them your CPU fan is acting screwy. It's still under warranty - correct?
     
  15. lazmeister thread starter macrumors newbie

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    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #15
    Yup, I was actually thinking of this once i get the inverter board :p you read my mind!
     
  16. lazmeister thread starter macrumors newbie

    Joined:
    Sep 27, 2011
    Location:
    GTA, ON, Canada
    #16
    Looks like something may be wrong with either the Logic board or maybe the power supply? I would think the logic board controls the CPU fan? I installed the new inverter board and still no luck :(

    Will put everything back to factory and return it to Apple
     
  17. jenseng macrumors newbie

    Joined:
    Jan 30, 2012
    #17
    I assume they fixed it? Any idea what the issue was? I've got the same issue, but my iMac is just out of warranty. CPU fan maxed out but it's reading 0rpm, and problem persists even after fully reverting the SSD upgrade.
     
  18. jenseng macrumors newbie

    Joined:
    Jan 30, 2012
    #18
    Turns out my logic board needed replacing. My best guess is the some static discharge fried something when I did the SSD upgrade. It pays to be careful :(
     

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