The Apple Logic Board is similar to a computers “Motherboard” – computers main circuit board. It contains the main system memory and circuitry that control the disk drive, display, keyboard and peripherals. Apple Device users at home can look for signs of a failing logic board, such as – Mac will not power on, system running very slow, no sound and no video, Apple device overheats, scrambled image, picture and video, Mac super drive not working, blank or dark screen, dim screen, defective macs USB port, Dead Apple Device, graphics processor failure, system freezes or shuts down accidentally, freezing or hangs, issue with Wi-Fi connection. A white, gray or blank screen can also specify an issue with the logic board.