A woman who dated Gabriel Aubry just before Halle Berry hooked up with him tells TMZ ... she warned Halle ... Gabriel was a money-grubbing dog who had a thing for very young women.
Page Bogart -- an investment banker -- tells TMZ, "Gabriel's entire motivation has always been money," adding, "I tried to warn Halle early on but I guess she didn't want to believe it."
Page, who dated Gabriel five years ago, says he raged at her -- accusing her of leaking unflattering information about him to the media -- and she gave us one of his voicemails to make her point.
Page says she saw Halle at a Miami Beach golf club and told her all about Gabriel, to no avail.
Page says she knows when Gabriel started dating Halle, "He had a few Latin hoochies on the side," but Halle wouldn't hear about it.