I have a Mac Pro Intel processor that is about 5 years old. The original hard drive has been giving me some problems, so I bought a new drive today (Seagate 1TB) and am attempting to initialize/erase it but having no luck. When I attempt to do this through Disk Utility in my 10.4 install disk, it gives me the error message "Input/Output error." It also shows that the drive is 7.3 TB, which it obviously is not. At the advice of a Mac friend, I tried to initialize it using the 10.5 disk. That disk immediately recognized it as 953 GB or so and initialized it for me. I named the drive "Seagate" and then attempted to install 10.4 on it by switching the install disks one more time. But the system did not recognize the drive at all. So I went back into Disk Utility, which showed me two icons for the new drive....the 7.3 TB icon and then inset an icon for "disk0s1." I attempted to erase the latter but with no success. (It simply said it was "unmounting" but nothing happened, so I rebooted.) I then tried to erase the drive again with the 10.4 Disk Utility but it failed. I need to run 10.4 because many of my programs are not compatible with 10.5. Does anyone have any ideas about how I might get this drive formatted for 10.4? Thanks in advance!