I fully opened the pc, finding that the keyboard has a very hard to manipulate orange flat panel cable FPC. I noticed that it had been bent quite substantially and I thought there might be a short in it. I flattened it and then went to look at the interior of the system. After a full investigation it was physically still in great condition but still rebooting.
I reset the NVRAM and PRAM by starting the pc with APPLE + OPTION + P + R, which didn't solve the reboot. I checked in single user mode, APPLE+S on start, and tried mounting the drive, but it was extremely corrupt and no third party software was loading at all. Sometimes this is because your processor in your Apple is not compatible with the bootloader on the cd/dvd you have. Yes, they are not bootable on purpose, marketing and control.
So, with a retail copy of Leopard, I setup the system, and deleted the partition, creating a new one. I then installed the OS and there wasn't a single problem. So, remember, borrowing OEM dvd install discs not for that specific apple will not work usually. A retail one is unlocked for all processor variants of the generation(s).
