VERY noisy 20" iMac after PMU reset...

Discussion in 'iMac' started by Huw, Oct 20, 2006.

  1. Huw macrumors newbie

    Oct 18, 2006
    I've just been on the phone with apple, following the probems I've had with my iMac randomly switching itself on at night... anywaym they told me to reset the PMU (the unplug, and pressing the power button while unplugged etc), and that maybe the reset would fix the problem.

    Anyway, after doing the reset, the fan on my iMac seems to be stuck on full speed, and is making so much noise its rediculous!!

    Is this normal after a PMU reset? Will the fan shut up after a while? or should I just give apple a call back?

    Cheers :)
  2. Viira macrumors newbie

    Oct 20, 2006
  3. iMeowbot macrumors G3


    Aug 30, 2003
    Here is the reset procedure for the iMacintels. SMC is what those wacky kids are calling the PMU now.
  4. Huw thread starter macrumors newbie

    Oct 18, 2006
    What happens say, if the person that I phoned at apple told me to hold the power button down while plugging it in, and since doing so, the fan wont switch off?

    Will holding down the power button fry the PMU/SMC or something? is there anyway to fix this?
  5. iMeowbot macrumors G3


    Aug 30, 2003
    I don't think anything has been fried, the full speed fans seem like a default that would be safest for keeping the insides cool.

    By the way, that procedure above is for the Intel iMacs, is that what you have? If you have a G5 model, here is the SMU reset procedure (SMU is yet another wacky name for a PMU).

    Why not try the documented reset for your model and see what happens? Maybe that will be the end of the problem and you won't have to worry more.
  6. Pete Dog macrumors newbie

    Nov 12, 2006
    thanks imeowbot

    Wow thanks I have an intel based imac which i thought for a while was a G5 so I was following the instructions for the G5 smu-or-whatever-it-is reset. the fans went wild! but by following the link above and doing the correct reset for intels, it's quiet as a mouse-ish. the moral: don't mistake your intel for a G5.

Share This Page