Fans run at full speed after computer turns on.

[gersten hay]

iMac iOS OS X 10.7.5. ; 3 yrs old
The noise is unbearable.
I have tried plugging it off/on, w the power cord, resetting SMC and NVRAM-nothing. Also, after I put it
to sleep mode it goes normal, but then goes back to sleep mode every 5 sec until is restarted.
Current values show, left fan: 998 RPM
RIght fan: 1256 RPM

Please help, I'm not a pro so use basic language, please.

 

[honestone]

First, did you follow this procedure for resetting the SMC?

http://support.apple.com/en-us/HT201295

Next, if there are still fan issues, re-boot the machine, do not launch any applications, then go into Activity Monitor (located in your /Applications/Utilities folder) to see if there is a process (or processes) that is using quite a bit of cpu resources.

Finally, you can download the free program smcFanControl, from here:

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

 

[gersten hay]

Yes, i have done all of the above, still no progress.

 

[honestone]

Yes, i have done all of the above, still no progress.

What does Activity Monitor show?

 

[gersten hay]

CPU? Nothing seems to over exceed. Could it be a disk usage, I hav e 19.8 GB free and 480 gB space utilized; mostly film and video.

 

[honestone]

Activity Monitor also shows disk usage. See if that is showing anything "strange".