Rev A is the 16/64 motherboard and Rev B is the 64/256 motherboard. ROM version does not affect this (most rev A owners upgraded their BIOS anyways).Hey guys. I am still working on my 5150 early model (would it be a Rev B if its a 16KB-64KB board with the Oct 1981 bios as opposed to the April 1981 bios?). Anyway I had a general question. Been doing alot of repair work on my 5150's and 5160's in the past few weeks. I have one board that came out of a 5150 that I am not sure is authentic. How can you tell if a board is IBM or Clone?
A true IBM board will have a silkscreened part number on the board that can be researched/verified. If in doubt, you can start a thread with a pic and let the experts in this forum weigh in.