Ballmer’s relations with the board hit a low when he shouted at a June meeting that if he didn’t get his way he couldn’t be CEO, people briefed on the meeting said. The flare-up was over his proposed purchase of most of Nokia Oyj (NOK1V), and part of an ongoing debate: Should Microsoft be a software company or a hardware company too?

Several directors and co-founder and then-Chairman Bill Gates — Ballmer’s longtime friend and advocate — initially balked at the move into making smartphones, according to people familiar with the situation. So, at first, did Nadella, signaling his position in a straw poll to gauge executives’ reaction to the deal. Nadella later changed his mind.

This is certainly not the first clash Ballmer had with the Microsoft Board, but it had to be a contributing factor to the splintering of that relationship.