I have the G5 2.7 Dual Ghz (Got this computer used a little while ago) This is the pre-intel (I believe nearly the last one made before the change) The computer has worked great for a few months until this morning. Now on restart it starts to boot up, but after 1-2 minutes reboots again (before ever getting to the blue screen) and this keeps happening over and over in a loop. I tried resetting the PRAM to no avail. I am suspecting something happened when my son tried to copy some music files from a thumb drive yesterday (he was unable to do so and was getting some sort of "damaged Macintosh HD" message) I didn't worry too much about it at the time. Also recently we've been powering down ALL our computers TVs etc. every night to save on our electric bill, so like our habit, we shut the computer down last night and this morning --- the problem began. I don't own a Leopard system software DVD but was wondering if I should go buy it and try a system install. Or if I should get it into a repair shop. Obviously I'm super concerned right now about a ton of data/files I don't want to lose. Thanks for any help!