Well ODB died of drug overdose, I found an article from a few months back on mtv.com:
"Ol' Dirty Bastard Died From Drug Overdose, Medical Examiner's Office Says
12.15.2004
Rapper found to have died from fatal mixture of cocaine, prescription drug Tramadol.
Ol' Dirty Bastard (file)
Photo: Evan Agostini/Getty Images
Over a month after Ol' Dirty Bastard collapsed and died in a New York recording studio, the cause of his death is finally known: a drug overdose.
According to a spokesperson for the New York Medical Examiner's Office, Ol' Dirty Bastard, born Russell Jones, was found to have died from a fatal mixture of cocaine and the prescription drug Tramadol, a synthetic opiate that is usually prescribed to treat severe pain. His death is being ruled an accident.
ODB has had a well-documented history of drug abuse, though in 2003, following his release from prison after serving a two-year sentence on drug charges, he had publicly professed to be drug-free.
On November 13, ODB collapsed after complaining of chest pains while working at the old Wu-Tang Clan Studios on West 34th Street in New York, a day after missing a Wu-Tang Clan reunion show in nearby East Rutherford, New Jersey"