Ok... I know that the intel iMacs are not supposed to be user-serviceable, but when the hard drive in my brother's computer died I decided to try swapping out the drive on my own. It was out of warranty anyway... So, I spent most of the day finding the right tools and following instructions found online and finally got the drive replaced with a new one (actually an extra drive pulled from my G5 tower). So, I got the new drive installed, set the LCD screen back in place, and decided to test it before trying to get the outer case back into place. Booted it up and... nothing. I hear the fans start up, but the light just starts flashing and the screen never turns on. Any ideas? FYI: I've never tried fixing an iMac before, but I've troubleshooted enough Macs to know that the hard drive was the problem... You could hear the drive clicking on startup and it would go to the "missing system folder" icon. It also refused to boot from an OS X install disc, but did boot from an OS X system on my external hard drive. When doing this, no internal hard drive showed up, not even in the system profiler as a disk that could not be mounted. Any help would be greatly appreciated!