"It was a 1963 356. It was on the street in Santa Monica with a 'For Sale' sign," he told CNN Style presenter Derek Blasberg. "I'd just finished a movie called "Can't Buy Me Love," and I spent my entire paycheck on that car."
Since then, Porsche has been one of the former "Grey's Anatomy" star's favorite marques. It's a fitting pair, too -- since 1948, Porsche models have claimed 30,000 racing victories, and, for the last 10 years, Dempsey has competed on the track himself, both as a driver and as co-owner of Dempsey Proton Racing.
In 2015, the team won the Fuji round of the FIA World Endurance Championship, and came in second in their class at 24 Hours of Le Mans -- driving Porsches in both races.
"The whole concept and design behind Porsche was to go racing and performance. That's really the legacy," he said. "I like to drive them, and you want to look at them because they are sculptural, they're beautiful to look at... You look at the Porsche line, it's just so identifiable, and it's so iconic."
Watch the video above to find out more about Patrick Dempsey's adventures on the race track.