Rick James, the self-proclaimed "king of punk funk" whose brash, boisterous, self-destructive life epitomized the title of his greatest hit, "Super Freak," died Aug. 6 at his home near Universal City, Calif. According to Sgt. Catherine Plows, a Los Angeles Police Department spokeswoman, the 56-year-old Grammy Award-winning entertainer died of "a preexisting medical condition."

Capt. David Campbell, spokesman for the Los Angeles County coroner's office, said the official cause of death is pending the results of a toxicology examination.

In the late 1970s and early 1980s, Mr. James had a string of manic and sexy R&B hits and was widely credited as the savior of Motown Records. His 1978 debut album, "Come and Get It!," which sold more than a million records, featured the hit "You and I," as well as "Mary Jane," the funk artist's paean to marijuana.

Mr. James reached superstar status with his 1981 album "Street Songs," which had partygoers across the country gyrating to the hits "Super Freak" and "Give It to Me Baby." The album sold 3 million copies.

With his cornrowed hair festooned with beads and his sequined spandex suits, with his down-and-dirty lyrics about "a very kinky girl, the kind you don't take home to mother" and a swaggering, strutting, drug- and alcohol-fueled "livin' large" existence, Mr. James was an explosion of decadent excess, yet for much of the 1980s, the hits kept coming.

His follow-up to "Street Songs" was "Throwin' Down" (1982), which featured the hit "Dance Wit' Me." The title song of his 1983 album "Cold Blooded" (1983) topped the R&B charts; the album also featured his duet with Smokey Robinson, "Ebony Eyes." In 1985, his song "Can't Stop," from his album "Glow," was featured in the blockbuster summer movie "Beverly Hills Cop," starring Eddie Murphy.

Mr. James wrote and produced hits for Murphy and such other artists as the Temptations, Teena Marie and the Mary Jane Girls.

Mr. James won a Grammy in 1990 for Best Rhythm and Blues Song for "U Can't Touch This," on which MC Hammer sampled "Super Freak."

Mr. James's wild rise came to an ignominious halt in 1993, when he was convicted of assaulting two women. The first attack occurred in 1991, when he and girlfriend Tanya Anne Hijazi restrained and burned a young woman with a hot crack pipe during a week-long cocaine binge at his house in West Hollywood.

He was free on bail when the second assault occurred in 1992, in his West Hollywood hotel room. A music executive, Mary Sauger, testified that she had gone to his room for a business meeting with Mr. James and Hijazi and that the couple beat her and held her prisoner for 20 hours. Mr. James could have been sentenced to life in prison had he been convicted of a torture charge.

Mr. James spent nearly three years in Folsom State Penitentiary.

"Cocaine is a powerful drug," Mr. James told a reporter for the Detroit News this year. "We would eat dinner and do cocaine. We didn't know anything about the Betty Ford Clinic then. The biggest mistake I made is that I tried to become my alter ego. I wanted to be Rick James, wild man, party machine, lady slayer, and the cocaine told me I could. I forgot that I was James Johnson, a nerdy kid, who grew up reading 'Dante's Inferno' on Saturday nights."

James Johnson was born in Buffalo, the third of eight children to Betty Gladden, a deeply religious woman who worked as a maid and numbers runner to support her family after the children's father abandoned them. Court records depicted Mr. James as an abused child who first experimented with cocaine at 14 and who spent half his adult life as an addict. He started using marijuana and heroin in his mid-teens.

He spent time in two juvenile homes for stealing cars before he found music. After leaving high school in 1964, he enlisted in the U.S. Naval Reserve for a year and then moved to Toronto, where, with Neil Young, he formed the rock group the Mynah Birds.

His music career exposed him to more drugs -- and more money to indulge his habit. The Los Angeles Times, relying on information in Mr. James's court file, reported that by 1991, he was taking as many as nine Halcion sleeping tablets a night and spending as much as $1,000 a day on cocaine.

Released from prison in 1996, Mr. James came out with a new album the next year, but his comeback stalled when he suffered a stroke while performing at Denver's Mammoth Events Center. The stroke was the result of what doctors termed "rock 'n' roll neck" brought about by an excess of head twisting during the show. The violent action, exacerbated by an encore performance of "Super Freak," caused two blood vessels to burst. Mr. James had to undergo six months of strenuous physical therapy. He suffered migraines and had to learn to walk again.

The next year, Mr. James underwent hip replacement therapy.

In recent years, a more sedate Rick James had attempted another comeback of sorts, touring with former girlfriend Teena Marie. This year, he poked fun at his outrageous '80s lifestyle by appearing in a popular skit with comedian Dave Chappelle on Comedy Central.

Last month, he performed his hit "Fire and Desire" with Teena Marie at the BET Awards and had finished an album scheduled for release next year. He also was in discussions about a movie based on his life.

Survivors include three children and two grandchildren.

Rick James, in June at the BET Awards, was best known for the 1981 hit "Super Freak." He was 56.