PieterErnst 0 Newbie Poster

Two of my G5 started acting weird all at a sudden. Not want to open apps or flashing windows. I then upgraded both to 10.4. (tiger) The installation starts and then crashes.
Tried different install discs and it still happens. Then installed new drive thinking that it might be a hard-drive problem, same thing.
I then installed the software by starting up the G5 as firewire drive. Run the install but after restart it just hangs.
After restarting several times it boots up and then freezes while navigating.
Any ideas?