Chosen Solution
Hello everyone! 4 months ago my 2008 imac 8.1 20" EMC 2210 started shutting down after it had been working for about one hour. Right now its shutting down after 30 minutes, but sometimes much faster.. When is shuts down, first the screen goes black, but the system keeps on going. A couple of seconds later everything just shuts down and the computer tries to reboot a couple of seconds later.. The diagnostics LEDs, all 4 of them are on when the iMac is running. As soon as the screen goes black, the 4th LED goes out. After a couple of seconds they all go out, except for the first LED. I have done the following:
- Cleaned the fans
- Checked the RAM
- Booted in safe and single user mode
- Performed a hardware test, no issues
- Hardware test uitgevoerd, geen issues
- Tried smcFancontrol for keeping the CPU temperature low
- SMC reset
- PRAM reset None have showed any improvements.. Although when using a fan on the back of the iMac it seemed to last a bit longer.. Does anyone have an idea? Thanks!
Once you get the external monitor connected keep an eye on it so when the internal display dies is the external still running before the system restarts. If you still have an image then the display is bad if it doesn’t then the power supply is bad. While your at it I would pull the heat sinks off and apply a fresh coat of thermo paste on both. Given the age of the system this will help keep it cooler.
You may have a power supply issue. Also, if smcfancontrol says the temperature is a really high one, that could be your problem.
I had this problem, Tried several things I did notice it seemed to be related to Foxfire crashing on me I have stopped using Foxfire… but I also - under System Preferences, I made it so my computer would never sleep. Still have the screen saver
