Just a hunch, but my years of repairing experience are telling me that the capacitor in the pic just may be a good place to start. 
**Update** Finally got around to pulling pieces from another A4000. Turns out the
processor card(A3640) is bad. Despite the fried cap the mother board works with a good
processor. But Im sure that bad cap effects some functionality. At least the MB isn't
completely shot.
Thanks all.
Rich