Fan at max speed, vertical lines, burning smell
My Early 2009 iMac (3.06 GHz Intel Core 2 Duo) has recently had an extremely loud fan. Using a fan utility I can see that its the CPU fan that is running at max. After a period of time, the screen will go to vertical lines and fan is off. I'm wondering what makes the fan run high in the first place- and why does it shutoff eventually?
How can I diagnose? I'm unable to boot into diagnostic mode, that appears to be something added in later models.
Is dit een goede vraag?
try this, Unplug the power from the back of the computer wait a couple of minutes and then plug it back in and restart the computer