[neoapple]

So I read more and more about issues with the new Alu iMacs. I have a new 20" iMac that has been having issues. I've read mostly about graphic card related issues. Issues with graphical glitches followed by freezing.

My iMac is not doing that instead it has been shutting down randomly. About once or twice a week. I have done a clean install of leopard and installed the iMac update that Apple recently released and I still have the issue. For the first time on this machine I did something that worked the video card.

I played a 3D game in windows via boot camp. After restarting to get back to the Mac OS the fans started going full-blast "hoover" action. The top back was very hot in the spot where I believe the video card is. I shut down last night this morning still full blast suction from the fans despite the air coming out no longer being hot.

Has anyone had this issue? What is wrong with these machines?

[mduell]

Poor choice of GPU (the entire HD 2000 series is a performance flop) + poor drivers... and possibly not enough cooling.

[ghporter]

...But (I hate to have to repeat this all the time) keep in mind that most people will not post "gee my new computer is so great, I am so very glad I bought this particular model!!!!" Most of the time, all you'll see is negative reports because people (like me) without a bobble or glitch just keep using their computers. Maybe we think it would be gloating to say "gee this is so great!"

mduell points out that the GPU is no prize winner, that some of the machine's drivers are less than great, and that sometimes there might be some cooling problems. Maybe so. I don't play games on my iMac, so I don't run into GPU issues, I haven't had any problems I could attribute to drivers (no problems at all, in fact), and I've never had any heat issues. Maybe I'm gloating now. But I wouldn't shy away from an otherwise solid machine just because all you see online about it is people complaining. You'll note that many of these complaints can be boiled down to "I knew that it had particular hardware but I bought it anyway, and now that hardware isn't any better than when I bought it." To which I say "tough."

[mduell]

Originally Posted by ghporter 

mduell points out that the GPU is no prize winner, that some of the machine's drivers are less than great, and that sometimes there might be some cooling problems. Maybe so. I don't play games on my iMac, so I don't run into GPU issues

Games aren't needed... IIRC even previewing the screen saver will crash one of the afflicted Aluminum iMacs. Are some of the current iMacs problem free? Sure, but the problems are widespread.

[neoapple]

I unplugged the machine and restarted; now the fans are normal. iStat now reports the fan speed correctly again (it did not before) the machine is now normal. I fear that the machine may have hardware issues that will continue. I will be buying Apple Care soon! It has bailed me out before.

As for negative posts not representing all user, I agree. Most people don't open threads to simply say my iMac is awesome. Yet, there does seem to be a hardware related defect with the 1st gen 20" Alu iMac. I am a bit worried as my last iMac was the 1st gen G5 iMac that suffered with hardware issues with bloated capacitors, bad power supplies, and ruined logic boards. My family had all 3 happen to our two G5 iMacs.

[dowNNshift]

If you're continually having problems or suspect something isn't right, take it to your local Apple Authorized Service Provider or Genius Bar.
They'll run a proprietary Apple diagnostic on it and will test multiple components of the machine. The best part is since it is a new machine if they find any hardware problems, you'll get them fixed free under warranty (provided its not abuse).

[mduell]

New fix out... Apple - Support - Downloads - iMac Graphics Firmware Update 1.0