I am reposting my question from Apple Discussions to see if someone here may have a little more insight into the problem. Here is the thread:
http://discussions.apple.com/thread.jspa?threadID=2545341&tstart=0
To update.... applications will no longer open. Just my desktop photo with nothing but the dock appears. The fans will occasionally come on full tilt and run for awhile that way and eventually slow down. Back when Temperature Monitor still functioned I was getting some pretty high temp readings, in excess of 75 degrees C. Just this morning I tried to run TechTool 3.1.3 from my iBook (target disk mode). the iMac's HD mounted on the iBook's desktop but TechTool was unable to detect the volume.
At this point, I have the back cover off of the iMac and am looking at the capacitors. Some of them look a little puffy around the crosses compared to the rest. I'm wondering if it would be worth the cost to replace the caps?
I am grateful to anyone who is willing to take the time to read and give me some input on this issue.
Thankfully,
Randy