Currently Being ModeratedApr 28, 2012 11:21 AM (in response to PattyCakez)
It may eventually sory. That was a problem back in the day. They overheat and melt the monitor. Bad design from apple. To compact and not enough place for heat to escape. In the mean time try blowing an external fan on the back of the monitor. See if the cold helps keep the temp down.
Yes, as that model ages, it tends to have heat issues. Ours starting doing thermal shutdowns after I installed a larger and faster hard drive that, presumably produced more heat than the original 10G drive.
Ours worked well enough in mild weather but our daughter had it in her apartment in Portland OR drung a heat wave. It was commonly 85-90F inside her appartment in the afternoon and that's when the iMac decided it was not going to work well any more.
The particular part that seems to suffer from the heat is the power/analog/video board--or "PAV" board. Once cooked it seldom recovers, and new PAV boards have not been built in years; there's little chance of finding one that has not already been "in the oven."
You can try active cooling. Find a laptop computer cooler pad with one big fan in the middle. Avoid those with two fans offest to the outside--you want something with a centered, powerful fan. Confirm that the fan blows air UP (some blow down). Position the iMac on the cooler pad so the fan is centered over the lower vents.
Another active cooling solution is ugly but actually works well. Some people have bought a large 120mm fan used in cooling big tower-type computers and screwed it to the outside of the upper exhaust vent so it pulled air from bottom to top. Works a trick but tends to sully the simple and attractive lines of the CRT iMac. However, if function is important, this is best way to get enough cooling to prevent further heat damage to the interior components.
Currently Being ModeratedApr 29, 2012 11:01 AM (in response to PattyCakez)
80F/26C isn't really that hot for the drive, which is the only sensor on that Mac. It's actually quite cool. I have no idea what the CPU may be doing on mine.The drive is all the way down at the bottom of the case and may not be a good proxy for that. My drive temps stay around 36-39C. I think my Seagate 160 GB drive runs cooler than the original 10 GB.
It's the heat at the top that really matters. As Allan explained, it's the PAV board that takes the hit. My G3/400 is still running OK, but I never use it in hot weather and I run a cheap clip-on fan aimed at the exhaust at the top to move the heat away from there, from about 2 or 2 1/2 feet away. Since the fan has an AC motor, if I set it any closer it causes a magnetic disturbance in the CRT (the picture tube) and causes it to shimmy. But it seems to do the job, knock acrylic.
One of these fan suggestions might help.Late 2009 iMac 21.5, Mac OS X (10.6.8), iMac G3/400 10.4.11
Currently Being ModeratedApr 29, 2012 11:10 PM (in response to PattyCakez)
Thank you for your help, everyone. I placed a small fan at the back of the computer where the VGA plug is and it stayed at a cool 65 °F for a whole hour with no blackouts!!!! If only Apple had put a fan there in the factory it would have extended the lives of so many beloved G3s.
Thank you so much for your time and know-how!