When a brand new John Deere tractors breaks down, you need a computer to fix it. When a John Deere tractor manufactured in 1979 breaks down, you can repair it yourself or buy another old John Deere tractor. Farming equipment—like televisions, cars, and even toothbrushes—now often comes saddled with a computer. That computer often comes with digital rights management software that can make simple repairs an expensive pain in the ass. As reported by the Minnesota StarTribune, Farmers have figured out a way around the problem—buying tractors manufactured 40 years ago, before the computers took over.

“There’s an affinity factor if you grew up around these tractors, but it goes way beyond that,” Greg Peterson, founder of the farm equipment data company Machinery Pete told StarTribune. “These things, they’re basically bulletproof. You can put 15,000 hours on it and if something breaks you can just replace it.”

The tractors manufactured in the late 1970s and 1980s look and run like modern tractors, but lack the computer components that drive up costs and make repair a nightmare. That’s made them popular at auctions around the American midwest. A Nebraska area auctioneer sold off 27 older model John Deere tractors in 2019. The old work horse tractors are so popular that one with low mileage can sell for tens of thousands of dollars. A 1980 model with 2,147 hours of use sold for $43,500. A 1979 model sold for $61,000.

That’s a lot of cash, but it’s still cheaper than a new model which can run between $100,000 and $150,000. The price is nice, but avoiding the computer components of the newer models saves money in the long run. “The newer machines, any time something breaks, you’ve got to have a computer to fix it,” Mark Stock, co-founder of BigIron auction told the StarTribune.