Overheating , fans running high , shuts screen off after 15 mins
I have a mid 2007 imac 24" intel duo core
My problem is all of a sudden it started the fans running high, runs for about 15 minutes and then the screen shuts off. The fourth led goes out and that is it, everything stays on and the fans are still on high.
Also I took it apart and blew out the fans and dust ( it wasn't that bad, but I could not get at the fan behind the main board yet )
When it is running nothing feels hot on the back or front , but I did notice that the upper left back corner was extremely hot and now it is not. Could a faulty sensor be the problem?
Here is a read out of my settings
HD. 38 degrees Celsius
Airport card. 55
GPU diode. 126
GPU heatsink. 126
HD bay. 41
Optical drive 699 rpm
Hard drive 1291 rpm
CPU fan 3309 rpm
Also it does not need to be unplugged to restart.