So, I have gotten an anti virus program, and have searched my computer and found nothing. What happens is that my iMac G5 will randomly shut down. It will just turn off randomly. It seems like it happens if I leave it on for a prolonged period of time...and after a while...it will just turn off. And it has been happening more recently. I have downloaded stuff using torrents and azureus...and when i do this i leave the computer on over night and just let the screen sleep. So, I figured it must be azureus or the torrents im downloading. However, just recently, azureus is certainly closed...and my computer will still randomly shut down. Today it has happened at least 8 times. I am running the latest version of tiger, have repaired disk permissions and everything else. I am very confused. Any advice?