N70 White screen and Hanging All Hardware Solution Here
If APE regulator is damaged or rusted then apply jumper 1 .
If SYNC/MODE SW is damaged or rusted then apply jumper 2 .
If both or for not wasting time then apply both jumpers .
& The advantage here is both jumpers can be made with a bit solder no need for wiring as both two jumper points are so closed.
Otherwise, it may be APE combo flash IC or processor OMAP fault (unsoldered or damaged) .