I'd never noticed the extra pins!
From: SciArt-L Discussion List-for Natural Science Illustration-
[mailto:[log in to unmask]] On Behalf Of James A Perkins
Sent: Thursday, 20 June 2013 6:57 AM
To: [log in to unmask]
Subject: [SCIART] USB 3.0 was Re: [SCIART] external hard drives
There's actually an important difference in some of the connectors.
The flat connectors that you usually associate with USB (called "A"
connectors) appear identical from the outside, but the USB 3.0 connector
has five extra pins inside. The plastic part inside the USB 3.0 connector
is also color coded light blue (as opposed to the white or black plastic
piece inside the USB 2.0 connector). You can plug USB 2.0 devices into USB
3.0 ports. You can also use a USB 2.0 cable to connect USB 3.0 devices to
older computers with only USB 2.0 ports. In either case, however, you'll
only get USB 2.0 speeds since the USB 2.0 connector lacks the extra pins.
The only way to get the added speed of USB 3.0 is to connect a USB 3.0
device to a USB 3.0 port using a USB 3.0 cable.
You may have also seen little square connectors for some USB devices
(called "B" connectors). These ARE shaped differently between USB 2.0 and
3.0. The USB 3.0 type B connector has an extra extension on it. With these
type B's, you can plug a 2.0 connector into a 3.0 port, but not the other
I don't think I'm explaining this very well, so watch the following video
if you want to see what I'm talking about:
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