I just purchased an indigo 400 MHz iMac g3, and noticed that after it's been sleeping for about an hour, it randomly shuts down. The first time I noticed I was out all day, so I couldn't see how long it took for this to happen, but now I think it took about an hour. Does anyone know what could cause this? Could I fix it? I know it's an old machine and it's bound to malfunction, but I had some plans for this thing. Thanks for any help you can provide.