Ok, so I hear conflicting stories about whether you can or cannot upgrade an early 2008 24" iMac's GPU.
Assuming you can, is the 8800 the limit? Mine has recently worn out. I hear the 8800 is now known for wearing out quickly and getting heat damage. Either I get Apple to repair it or do it myself (as my AppleCare has run out) but I don't want another NVidia GeForce 8800 in there due to its known faults.