For years I've wondered why people buy Mac Pro systems at all. As I wrote in early 2009, performance tests show an iMac is faster than a Mac Pro, so given the fact that a Mac Pro system is much more expensive than an iMac, and doesn't include a monitor, why would anyone buy a Mac Pro?
One reason I've learned that people might buy a Mac Pro is that an iMac quickly turns into an indoor heating system under certain conditions, including watching video online, and watching DVDs. Whenever I watch a movie on Hulu, a baseball game on MLB.com, or a DVD, my 24" iMac gets very warm, and the internal fan(s) fire up to avoid burning down the apartment down, and the smell of burning plastic (or something else) begins wafting through the air.
So, if you're wondering why you'd buy a Mac Pro instead of an iMac, well, that's one reason.
That doesn't sound good. I hope your computer is okay. I just bought a MacBook Pro, because I love laptops, being that I travel so much to Doctor's appointments. So of course, I need something to do during the wait. But so far I love my MacBook Pro. :)
Yes, it is a little scary when the iMac gets that warm, but it does keep running. I have an old MacBook Pro, and love it. I'm sure yours is terrific for those nice long doctor-office waits. Cheers.