My 2 year old imac recently started dramatically slowing down. Eventually the computer would just show a question mark on the gray start up screen. I put it in target disk mode and determined that the hard drive was failing.

Disk utilities showed internal hard drive as "media"

Well.. seeing how my imac was out of warranty, I decided to replace the HD myself. Easy job. Formatted the drive to GUID and installed leopard.

Now.... the computer goes to the gray screen then a message pops up saying to restart the imac. (Great)

Fearing this was a logic board issue, I put my other computer in target disk mode and boot from the the imac. It works just fine. In fact, im writing this thread from the imac. The hard drive shows up and I am able to put information on it.

I do not understand what the problem is if everything seems to be working. The imac will not do anything with the new hd.