Q I have been told that my Mac needs a new logic board, which seems very expensive. Is this different from the motherboard?

A In practice, these terms are interchangeable, and refer to the main printed circuit board that forms the heart of your Mac.

Motherboards are strictly speaking those that have smaller daughterboards attached to them, perhaps containing the graphics interface, memory modules, or similar. Apple uses the term logic board to describe the circuit board that houses the processor(s) and other electronic ‘logic’ components, as against an analog board that houses interface circuitry for the monitor and ports. This would make analog boards equivalent to daughterboards in more general terminology.

Sadly, replacement motherboards or logic boards are relatively expensive as they contain the most costly parts of the hardware.

Updated from the original, which was first published in MacUser volume 25 issue 19, 2008.