The Apple-1 computer is the first personal computer model ever sold. There are only 15 working original models left.

A rare Apple-1 computer built in Steve Jobs' garage in the summer of 1976 sold at auction this week for a record-breaking $905,000.

There are, at most, just 15 fully functional Apple-1 computers in existence. The high price tag — almost double the original estimated value — makes this particular Apple-1 model the world's most valuable computer relic and the most expensive Apple computer ever sold, according to Bonhams Auction House, which handled the sale yesterday (Oct. 22) in New York.

The Apple artifact now belongs to the Henry Ford Museum in Dearborn, Michigan. A representative from the museum outbid another interested party, who was not present at the auction, but used a call-in line to place bids. [Photos of Apple-1 & Other Items Sold at the Science History Auction]

The computer still has its original keyboard, power supply and monitor. Apple-1 expert Corey Cohen certified that the model is in excellent working condition and needed few replacement parts. The last Apple-1 that went under the hammer had a little more wear and tear; it sold for $387,750 during an auction held by Christie's in 2013.

The Apple-1 model is the first pre-assembled personal computer ever sold. As of January 2014, there were 63 remaining Apple-1 models, but as of 2000, only 15 were still in working condition. This model is from a batch of 50 computers hand-built by Apple co-founder Steve Wozniak in 1976, when Apple was just a fledgling company based out of a garage in Los Altos, California. It was sold along with a recording of a speech delivered by Wozniak at the Applevention Conference in 1980.

The computer was sold as part of a history of science auction. During the sale, a letter from Charles Darwin discussing the details of barnacle sex sold for $25,000, a copy of Darwin's "The Origin of Species" sold for $40,000, a collection of notes and books from the astronomer Johannes Kepler sold for $52,500, and one of the world's first electric keyboards sold for $20,000.

Follow Kelly Dickerson on Twitter. Follow us @livescience, Facebook & Google+. Original article on Live Science.