[iBook] G4 logic board???

[Samantha Cornell]

I just returned from vacation to learn that my stepmother has sent her 
G4 iBook in twice for logic board problems.  The first time, they 
replaced the logic board and the battery, but the screen went black 
again within a few minutes of using it after receiving the repaired 
iBook.

Has anyone else experienced logic board problems with the G4s?  I had 
hoped that they were confined to the G3s (we have two G4s in our house, 
and she has one too...so this could be a nightmare for us).

Thanks!

Samantha