In 2007, producer Omen reunited with producer 40 in the studio, this time asking him to bring Drake. Omen played Drake a song he had created for his own release, a track titled "Overdose On Life," and asked Drake to write to it. 30 minutes later, Drake had finished the "craziest 32 bar verse ever, and we laid it," says Omen.
Coincidentally, a few days after that, Omen got a call from an A&R at Aftermath Records, asking Omen for tracks for Dr Dre's upcoming "Detox" album. Omen told them about the very fitting "Overdose On Life," and sent it over.
Although "Overdose To Life" didn't make the cut for "Detox," Dre flew Drake and 40 out to the west coast off the strength of the track, where they remained for a couple of months working on music.
Source - http://www.billboard.com/news/drake-teams-with-the-dream-for-new-single-1004016173.story#/news/drake-teams-with-the-dream-for-new-single-1004016173.story