False overheat- Ideas?

[Nachtwulf]

So a couple of days ago, my imac (early 2007, yes I know it's old) started to believe that making it do anything whatsoever was causing it to overheat. Anything from browsing the web to running Warcraft (yes, the latter is taxing, but Facebook certainly isn't) causes the cpu temp to appear close to 200º and the fans roar up to 3600 rpm. Now the thing is... nothing is taxing the cpu most of the time (even WoW only runs the cpu up to about 35%) to cause this. The case is barely warm and the air that's being blown out is hardly tepid. It's obviously NOT really overheating, as it shouldn't by loading a simple webpage, so what's going on? I can't find any strange processes in Activity Monitor that might be causing stress, and like I said, the box doesn't feel hot anywhere on it.

Even right now, with nothing open except Chrome and this single browser window on a page that doesn't even have anything moving, the CPU temp is reading 201º and the fans at 3600. I do have SMCFanControl running, could it have gotten corrupted somehow? Is the temperature node on the logic board dead and I'm about to have a meltdown?

 

[honestone]

That's a bizarre issue, to say the least! But, first of all, do you have the latest version of SMCFanControl? It is 2.5.2, and you can get it from here:

http://www.macupdate.com/app/mac/23049/smcfancontrol

Secondly, if that does not help, try removing it, and see what happens.

Third, do you have a full system backup that was done at a time when things were more "normal"? If you do (and especially if it's a SuperDuper! backup (restoration is a breeze with that program!)), you could 1) completely wipe off your hard drive (that will also tell you if the hard drive is dying), and 2) do restore from that backup.

Fourth, if either you don't have a backup, or do not feel it will help, at least run Disk Utility in Recovery Mode to 1) Verify and Repair the hard drive, and 2) Verify and Repair permissions. That won't hurt, and again it will indicate the "health" of the hard drive.

You could also try an SMC reset, and reset the PRAM. Here is how you do each of those:

SMC RESET

• Shut down the computer.
• Unplug the computer's power cord and all peripherals.
• Press and hold the power button for 5 seconds.
• Release the power button.
• Attach the computers power cable.
• Press the power button to turn on the computer.

PRAM RESET

• Shut down the computer.
• Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
• Turn on the computer.
• Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
• Hold the keys down until the computer restarts and you hear the startup sound for the second time.
• Release the keys.

Finally, here are the results for a google search I just did on "iMac 2007 overheating":

https://www.google.com/search?q=iMac+2007+overheating&ie=utf-8&oe=utf-8