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USB 3 & USB 2

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USB 3 & USB 2

I understand that you can plug a USB 3 device into a USB 2 port and get USB 2 speeds but can you use a USB 2 cable to connect a USB 2 device in a USB 3 port?
I have searched Google but haven't found anything that states it is possible.
The reason I ask is I'm advising my mother on purchasing a laptop and the one I think is most suitable has 1 xUSB 2 and 2 x USB 3. Apart from requiring a wireless mouse which would be connected to the USB 2 she doesn't currently have any devices to attach but I have many old movies on a HDD I'd probably take round for her to watch and these drives are USB2.

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4 REPLIES
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Re: USB 3 & USB 2

I have 2 USB 3.0 ports on my PC as well as a number of USB 2.0. They are all full feeding USB 2 devices via USB 2 cables.

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rongtw
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Re: USB 3 & USB 2

usb 2 is compatible with usb3 and vice versa , only thing is you dont get usb3 speed with a usb2  Roll eyes
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Re: USB 3 & USB 2

Thanks.
What I did read, though, is that a USB 3 cable is not compatible at the device end due to a change in the number of connections (4 in USB 2 & 8 in USB 3).

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Re: USB 3 & USB 2

The device end of a USB 3.0 cable is a different shape and USB 3.0 uses 9 pins.
http://docs-europe.electrocomponents.com/webdocs/1023/0900766b81023ab9.pdf

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