I'm looking fore some help/opinions on a friends iBook G3 800/30GB/256MB/10.2.8. the problem is- when you press the power button, it powers on and you hear the (all is ok) chime. now sometimes it will boot perfectly fine and others you get nothing, just a blank screen. Now i know these things were notorious for logic board failure, but could this just simply be the HD, and if it is, how easy is it to change. any help appreciated.