Thanks for your thoughts, guys. You'll be interested to know that i've actually got the AppleVision 1710AV plugged into it right now (its working fine, btw). Anyway, with the machine running on an external display, and the internal display in standby mode (since its not plugged into anything), the machine is running noticeably cooler...its been running for a good 3 or so hours now, and when i put my hand on top of the iMac it still feels cool, like as if it hadn't been turned on at all. Since the analog board is on its way out, and its now Spring (which means in a couple of months it will be Summer) here in Australia, i'm thinking of leaving it like this for now...as it is, with the iMac on the floor and the AppleVision hooked up and on my desk in the place where the iMac normally goes, its fine for now.

Btw, i must say...it sure is nice to be able to run OS X at 1280x1024 instead of the puny resolution of 1024x768 that i'm used to!