A fully operational Apple-1 computer that Steve Jobs himself sold out of his parents' garage in 1976 will hit the auction block in December with an estimated selling price of $600,000.

The Ricketts Apple-1 computer, named after the original owner, Charles Ricketts, will be sold on Dec. 11 and is the only known surviving Apple-1 computer as sold by Steve Jobs himself.

"It all started with the Apple-1 and with this particular machine," said Andrew McVinish, director of decorative arts at Christie's. "When you see a child playing with an iPad or iPhone, not too many people know that it all started with the Apple-1. So to be able to own a machine that started the digital revolution is a very powerful attraction."

While $600,000 may seem like a lot money, it doesn't seem exorbitant compared with the $905,000 that the last Apple-1 computer sold for.

Bruce Waldack acquired the computer in 1999. Waldack was an entrepreneur who bought it after he had just sold his company, called DigitalNation, then eventually lost his fortune and died in 2007. Robert Luther, a collector in Virginia, purchased the computer at a police auction in 2004.

"I knew it had been sold from the garage of Steve Jobs in July of 1976, because I had the buyer's canceled check," said Luther on a Kickstarter page requesting funding for a book on the computer's history. "My computer had been purchased directly from Jobs, and based on the buyer's address on the check, he lived four miles from Jobs."

It is currently estimated that less than 50 complete Apple-1 computers are still around. Many were likely thrown out by owners who had no idea of the historical significance that the computers would have one day.

This particular Apple-1 computer was serviced and tested by an expert, who was able to start up the machine and run the original software program, Microsoft BASIC. The expert was even able to run an original Apple-1 Star Trek computer game on the machine.

The computer will be sold with the canceled check itself, which was made out to Apple Computer by Charles Ricketts for $600. The label on the check says that it was "Purchased July 1976 from Steve Jobs in his parents' garage in Los Altos."

The check, along with another similar one, was used as evidence to persuade the city of Los Altos to make the Jobs family home eligible for a listing on the National Register of Historic Places.