Poyet replaced Paolo Di Canio as manager earlier this month after the Italian was sacked by the Wearside outfit.
Former Brighton chief Poyet admits the Sunderland role was one of eight jobs he was keeping tabs on in the hope a position might come available and that O'Neill spoke highly of the club.
Poyet and O'Neill met at the League Managers' Association's annual golf day in July, when both men were out of work and the Northern Irishman's praise of Sunderland helped convince him to go for the manager's job.
"I went to a meeting of the LMA in the summer and by coincidence I played golf with Martin O'Neill and took the opportunity to ask him 150 questions," said Poyet.
"He spoke very highly of the club itself and everybody here.
"Martin is a very honest person, a lovely person and he spoke highly about the chairman, the fans, the players and I also asked him questions I cannot reveal to give me insight into lots of details about the club.
"It was important to me to know his opinion with him having been here for a while.
"I used the opportunity of being with him for 18 holes to get information from him and I will call him now I have the job."
Poyet added: "Realistically, I knew there were say eight possible teams who might not start well where I might get an opportunity.
"Sunderland were one of them and then of course when they started badly, I paid particular attention to them, so I knew as much as possible about them.
"I know this club. I came here and played here and I have studied it and I know all about its fans and its history.
"Of course, that is no guarantee because they need to call you, they need to like you.
"I became aware of Sunderland's interest the other week and made it clear how much I wanted the job.
"Then I had to wait for the chairman (Short) to make his decision and be patient because that decision was not in my hands."