What's The Difference Between USB 3.1 Gen 1 And USB 3.1 Gen 2?

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husker

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So... a rounded version number such as "1", "2", "3" is not enough. Instead, we need to use a decimal to distinguish 3.0 from 3.1. But the next version can't be 3.2 or 3.1.1, they have to name it "USB 3.1 generation 2". What is next, "USB 3.1 generation 2 first cousin"???
 

InvalidError

Titan
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@husker what's next is USB3.2 which sorts out the connector alphabit soup by mandating Type-C exclusively. The confusing speed standard verbiage still applies though - which of 'high speed', 'full speed' and 'super speed' stand for what speed? Only the most astute tech enthusiasts know the answer without looking it up. I hate obtuse marketing names. Gen-1/2 may not look pretty but it is simple and unambiguous.
 
May 17, 2018
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USB is a joke... a committee and standards designed to confuse the sh*t of everyone, users and developers. And it isn't bad enough to develop for it you need to make sense of thousands of pages of nonsense but at the end of the day you have a box full of adapters and connectors that almost look the same but don't work together. Can we please just get a simple small unisex connector that plugs in either way both up or downstream and quickly and simply negotiate the protocol on connect? There is nothing high-tech about this, it could have been done when USB was introduced 100 years ago.
 

AnimeMania

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To me, the thing that is important is the color of the USB ports.

Red, Orange or Yellow - has extra electrical power that does not shut down when the computer is turned off, used to charge devices like phones
White - USB 1
Black - USB 2
Blue - USB 3.1 Gen 1
Greenish Blue (Teal) - USB 3.1 Gen 2

I am not sure if any motherboard manufacturers actually use the Blue/Teal colors to distinguish Gen 1 from 2
 

InvalidError

Titan
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Part of the reason USB is the convoluted mess it has turned into today is because it was originally designed to be a low-cost replacement for the dozens of proprietary and legacy low-speed serial/parallel standards scattered all over the shop back in the day. A short while later, the original "full speed" 12Mbps turned out to be insufficient for many mainstream uses and we got USB2 aimed at displacing FireWire 400/800 in the medium-speed external interface arena.

Much of this mess would have been avoided if USB had been designed with dedicated RX+TX pairs instead of time-shared multiplex over a single pair. But this wasn't compatible with USB's original objective of cheap cables, cheap connectors and cheap chips. So now we have those two dedicated RX and TX pairs, a bunch of auxiliary function pairs, the USB1/USB2 legacy pair and a couple of other things cluttering the type-C connector. Expensive connectors, expensive cables if you get fully wired ones, relatively expensive chips and circuit design if you want to support all functions at once.

To hell with USB's original mission of being cheap and cheerful.

I'd say we're overdue for replacing USB with an uncluttered external PCIe standard for high-speed external devices.
 

bachastain

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Feb 24, 2016
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I want whatever drugs the USB engineers are taking. Seriously, I have never seen so many horrendous decisions come out of a single group before. For god's sake, apologize for the lapse in judgment and rename USB 3.1 Gen 2 to USB 3.2. Do it before you rot the brains of our deeply confused youth.
 

InvalidError

Titan
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USB3.2 has been defined as USB with Type-C connectors and speeds up to 20Gbps in July 2017. 10Gbps per lane, two lanes in each direction, including all of the backward-compatibility overhead for USB1/2/3.0/3.1.
 

alextheblue

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That doesn't actually fix the biggest issue. What does a particular USB-C port support? Power delivery? How much / what profile? Analog audio (for one-port phones to use analog headphones without an active adapter)? What alternate modes? HDMI, MHL, DP, Thunderbolt? Active or passive cable required? Who knows!

I echo your sentiment that a PCIe based standard would be nice... as long as they can do longer than 1M passive cables (3.1 Gen 2).
 
May 15, 2018
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I know that there are certain motherboards (like the B350 Tomahawk) where all (USB) ports are red except for the gen 2 ones. Can't they just do it like it has to be?
 

InvalidError

Titan
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Nothing and everything, depending on the endpoint devices and cable. It is both a curse for making Type-C a 'standard' with no uniformity foisting the responsibility of figuring out what devices can work together as expected using what cables prior to purchase and a blessing for consolidating the 12+ different modern-day connectors.. DP, mini-DP, HDMI, mini-HDMI, micro-HDMI, USB 1/2 A+B+mini-B+micro-B+OTG mini/micro variants, USB3 A+B+micro-B, Thunderbolt, Lightning, proprietary power adapter, proprietary dock connectors and possibly a few more. We're basically back to 1995 with each device class having its own connector... and USB having the worst connector fragmentation ever seen in a 'standard' that I can think of. Yes, USB is truly abominable from that point of view.

For the external PCIe cable length, LTT did an experiment to see how many risers they can put between a PC and its GPU using high quality (sponsored) riser cables. The GPU ended up across the room before it would no longer work properly. I'd say ~3m is a pretty fair distance to go on passive risers without the expense of extra transceivers at cable ends or endpoint devices. On mobile devices with 10-15Wh batteries, you wouldn't want to spend an extra 2-5W on transceivers unless they were absolutely necessary either, so I'd leave transceivers on the cable if needed. This grants cable manufacturers the extra flexibility of matching chips to whatever media (50/75/90/100/110 ohms twisted pairs, flat flex, coax, MM/SM plastic/glass fiber, wireless, etc.) they want to use.
 

lhughey

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Feb 15, 2013
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@Husker "USB 3.1 generation 2 first cousin". LOL.
I agree with the thoughts of many here. You know it's bad when tech enthusiast have no idea of the difference.
 

ledhead11

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Oct 10, 2014
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I love the speed increases that have happened over time for USB but from port/plug variations and their naming schemes its become a huge mess ever since 2.0. Long before 3 gen whatever they started with standard/micro/mini/a/b/and other things I can't even remember. For a brief time when 3.0 came out it at least seems to taper off a bit and then 3.1 came out and its a mess again.
 

USAFRet

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We already had that. Firewire.
It lost out to USB in the external connection race.
 

InvalidError

Titan
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We already had that. Firewire.[/quotemsg]
FireWire had the 'A' and 'B' variants when FireWire doubled bandwidth by doubling the lane count. It also had 'mini' variants to accommodate smaller devices - my first laptop had a mini-1394a port. If it was still in active development in the modern mobile computing world, it'd likely also have acquired 'micro' A/B variants or even altogether new connector/cable spec similar to Type-C to accommodate devices with only one or two ports.

The only reason FireWire looks relatively clean compared to the mess USB has become with Type-C is that FireWire doesn't have alt-modes. Its only purpose was being a multi-master bus. The closest modern thing to FireWire today would be Thunderbolt but even that has become a Type-C alt-mode.

If FireWire was still in active development today, I bet it would have become a Type-C alt-mode too.
 

USAFRet

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Right.
The FW connection, being relativity fat, would have gone down the same road as USB, and gotten a really small variant.
Resulting in FireWire-C
 

ravewulf

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Instead of USB hi-speed/superspeed/superspeed+ they should've just used the numerical Mbps/Gbps transfer rate. People understand numbers a whole lot easier than marketing terms that need to be deciphered
 

Valantar

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Nov 21, 2014
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"The USB-IF never intended for the those terms to be used in marketing materials, though. To help clarify the two different speeds of USB 3.1 and the various other protocols that can run over USB connectors (eg, Type-A and Type-C), the group created terminology and visual branding. For example, USB 3.1 Gen 1 is “SuperSpeed USB,” and USB 3.1 Gen 2 is “SuperSpeed USB+.”"

Yeah, that makes total sense. Distinguishing between SuperSpeed USB and SuperSpeed USB+ at a glance is soooo easy. Of course. And easy to say! Just rolls off the tongue. And why is SuperSpeed faster than, say, Full speed? I've never - ever! - heard a single person use those "marketing terms" for USB standards. Ever. Get rid of them, please.

Separating technical terms and marketing terms like this makes no sense. We already had 1.0 and 1.1 too long ago for anyone to remember, 2, 3 and the next should obviously have been 4. Considering there is zero noticeable end-user difference between 3.0 and 3.1G1, they should have kept that named 3.0 and added a "rev. 2" in the documentation, while otherwise changing nothing at all from how it works today. Then they name 3.1G2 "4" (or at least 3.5 - "it's like 3, but faster") to make the 2x performance difference clear to end users. This would clear up any confusion, and honestly, placing the burden of ensuring compatibility and spec compliance on engineers is... their job. If there's zero practical difference between 3.0 and 3.1G1, what's the worst that could happen?
 

InvalidError

Titan
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USB3.0 uses the updated A/B/uB connectors. USB3.1 introduced the Type-C connector and its boatload of optional alt-modes still using the 2.0/3.0 specs for USB data. Too many physical and functional changes to still call it 3.0, but no changes to the core USB functionality (data transfer) to justify calling it 4.0, so the USB-IF went 3.1.

USB 3.2 sort of fixes the confusion as its 20Gbps speed is only possible with fully wired Type-C cables. It may generate frustration due to many cables only having one high speed pair in each direction as that's all that is required up to USB3.1-gen2. This means people who have a significant investment in USB3.1-C cables are likely going to bitch when they find out they need to upgrade to USB3.2 cables and keep track of those. Gotta love fragmented standards.
 

none12345

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Apr 27, 2013
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"I am not sure if any motherboard manufacturers actually use the Blue/Teal colors to distinguish Gen 1 from 2"

Mine does, ive got an asus prime x370-pro. The (2) 3.2 ports on the back are teal. The (5) 3.1 ports are blue. There is also a 3.1 type c that im not sure if its colored or not, cant see back there. The internal 3.2 header, 3.1, and 2.0 headers are not colored.

My usb sticks are also approiately colored.
 
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