Those new USB-C cords can fry your laptop

reversible usb

The gadget world is slowly adopting a new power cord standard called USB Type-C. They're small, multipurpose, universal, reversible and might fry whatever gadget you plug them into.

The advantage of the new standard is that USB-C isn't owned by any one company. That means anyone can make them for cheap. The disadvantage: They might wreak havoc.

Cheap power cords are nothing new. You can get cords that meet the old micro-USB standard for smartphones for a couple bucks on Amazon (AMZN).

But the new USB-C cords are capable of supplying way more power to a gadget than micro-USB. If you charge your smartphone by plugging your USB-C cord into your laptop, a faulty cord could drain far more power from your laptop than your computer is designed to supply, destroying it -- and your smartphone -- in an instant.

The cords are supposed to recognize what kind of device they're sucking power from. If the USB-C cord senses it's plugged into a wall socket, it should crank up the juice. If it's plugged into a laptop, it should sip power.

That's not what happened to Google (GOOGL) engineer Benson Leung. While testing Surjtech's 3M USB-C cord, his $1,500 laptop turned into a very expensive piece of toast. The cord had been wired incorrectly,

Related: This is the new USB connector - and it's reversible!

Leung took it upon himself to review USB-C cords on Amazon to help prevent faulty cords from ruining someone else's day.

"I have gotten fed up with the early cables from 3rd party vendors that so blatantly flout the specification and I want to take them to task," Leung wrote on his Google+ page. "You may not just get weird behavior from your devices with these bad cables... What some these vendors are doing is downright dangerous."

Buying more expensive cables is generally a good idea, based on Leung's research. But an expensive cord doesn't necessarily mean that your gadgets will be safe. And blindly spending extra money on a power cord a pretty dopey way to ensure that your laptop and phone aren't going to be destroyed.

The good news is that the USB-C standards-setting group, the USB Implementers Forum, is issuing a seal of approval for safe USB-C cords. Since those logos don't show up anywhere on Amazon's website, your safest bet might be buying cords at a physical store, such as Staples (SPLS) or Best Buy (BBY), where you can see the logo on the box.

And if you're an iPhone owner, you're safe for now. Lightning cords are certified by Apple (AAPL) (that's why they're so expensive), and Apple hasn't yet adopted the USB-C standard for its iPhones.

Safe powering!

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