(FORTUNE Magazine) – IF YOU HAPPEN TO DROP BY THE FORTUNE office these days, you'll notice the place is filled with moving boxes. After 19 years on the 16th floor of the Time & Life Building, the magazine will soon relocate one floor down. Change like this can be unsettling, but it can also make for a fresh start. I was reminded of that point during a conversation with hedge fund honcho Larry Bowman, who also decided to pack it in recently. Only a few years ago Larry was running one of the biggest hedge funds on the planet. Now Bowman, 46, has just finished returning his investors' money and is beginning a new phase in his life, allocating his own wealth to other hedge fund managers. "Investing in public tech companies is a young person's game," he says.

This is not a sob story, though. Bowman has amassed a fortune well into nine figures. Still, it's intriguing to hear from a man who rode the economic roller coaster in the front car. An ultraconfident, type A individual, Bowman graduated from Lehigh with a degree in engineering and went on to work at TI and Apple before getting an MBA from Stanford. He then joined Fidelity, racking up stellar returns as a tech-fund manager in the early 1990s. He jumped over to Tiger Management and then in 1995 struck out on his own, soon setting up shop in Silicon Valley. "Everyone else doing tech investing was an accountant sitting in an ivory tower in Manhattan or Boston," he says. The good news was that he had next to no competition, since there weren't really any tech hedge funds in Silicon Valley. The bad news was that raising money was hellish. "I put in $1 million, and it took me months to raise another $15 million," he says. "Nowadays any 37-year-old with an MBA who shaves can raise a billion."

Bowman started just when the tech biz exploded to the upside, which was tailor-made for his momentum style. His returns were eye-popping--up 92% in '95 and 71% in '96. Money poured in. Remarkably, by early 2000 Bowman Capital Management's assets had zoomed to $6 billion, reportedly making his operation one of the five largest hedge funds in the world. He became a player, opening up offices in New York and London and hobnobbing with Silicon Valley grandees, many of whom invested in his funds. Larry even turned up in a Frank Quattrone e-mail: "I just want to make sure that we are taking care of Larry Bowman properly," a CSFB underling wrote to Quattrone in February 2000. (Bowman says he doesn't "remember anything about that specifically, but we were generating huge commissions then.")

As for his own downfall, Bowman says, "The tech implosion was inevitable, but our implosion was totally under my control." Bowman says he made money in 2000 even as the Nasdaq tanked. But he started to fade in '01, especially after he got caught on the short side post-9/11 when the market rallied. He ended the year down 36%. Because of the so-called high-water-mark convenants in his fund, Bowman and his employees, some of whom were said to be discontented, would have to work without any incentive fees until the fund made up the loss (in this case, the fund would have to climb some 50%). Instead Bowman returned his investors' money--a cool $4 billion, he says. He made one more stab at running what he calls "friends and family money" in September 2002, but after returning mid-single-digit numbers in 2003 and being barely profitable last year, Bowman decided to pack up the old kit bag. "After 17 years of 24 hours a day, the pace is better now," he says. "I learned that volatility is just a euphemism for losing money."

ANDY SERWER, EDITOR AT LARGE OF FORTUNE, CAN BE REACHED AT ASERWER@FORTUNEMAIL.COM. READ HIM ONLINE IN STREET LIFE ON FORTUNE.COM AND WATCH HIM ON CNN'S AMERICAN MORNING AND IN THE MONEY.