Glad the chips arrived safely Lenoz.
I tested all of them before i sent them to make sure they were good , so you must have some other problem with the board.
As Steevsee said ,make sure that the 5101's socket is good , if in doubt put in one of the new ones i sent you.
I had a problem with a board once before like this and it was either IC27 (4071) or IC24 (7400) that was the problem...can't remember exactly as it was a while ago , and i wouldn't say for sure that changing them will fix your problem , yours might be something different.