Most of the iBooks with dodgy boards have no video at all. The problem is that the logic board flexes too much and the solder joints on the GPU pins break. Maybe yours only broke the ones it needs for the internal screen. Seems unlikely to me though. You'd be better off looking at the display cable, inverter cable, inverter board and reed switch.All of these are pretty cheap. However since pressing down on yours made it work for a while, it would seem to imply the logic fault. There is a temporary fix on xlr8yourmac.com somewhere which might prolong its useful life. You basically insert a small square of metal between the metal shield and the outer case to press down on the chip for you. Won't last for long if you continue lugging it around though.