Hi I am trying to upgrade my internal hard drive on my Imac 2.33ghz core duo computer. I bought a 1tb seagate drive and installed it, which was actually very easy much to my surprise, but after putting everything back together I put the installation disk in and when I got to the choose drive screen there was nothing there to choose. I talked with seagate and they said to check and see if the computer could handle a 1tb hd so I tried doing research and really could not find an exact answer so I bought another seagate 750 gb this time and the same thing happened. My questions are 1) does anyone know how large a drive I can use with the computer I have 2) can anyone give me help as to what I might be doing wrong if my computer should handle the 750gb seagate barracuda 7200.11 st3750330as 750gb 7200 rpm sata 3.0gb hard drive. Thanks and please I know all about everyone saying do not open your computer because of the warranty issues so please no replies about that. Thanks again