terrible feeling losing this baby to that, I applied presure to that spot and heard the chime, there was no screen light up, just went dead and off. You have solved this, its the board failure. Another mac that once seemed alive and well one day, dead, much like pets these older macs bite the dust way to early, I'll miss her.
When apple started up with their early models - they gave you a telephone help number for life! If only they would give a resonable repair program for life, have a department for vintage repairs! that would be so nice.
Someone needs to open a web page for mourning the lost old computers, you could leave a note about how this baby was with you thru so many things, then let her rest in peace.
Lovely iBook G4, you rest in peace now.