Why does the USB 2.0 exist alongside 3.0?

[Llewellyn Fernandes]

Hi,

 

Recently Huawei announced their new lineup of Matebooks with their "revolutionary" folding phone. Their Matebook 14 has both, Type A 2.0 and 3.0 usb's. Why? 

Wouldn't it be better to either provide a different port or just 2 USB 3.0 ports?

 

Here's Engadget's youtube link: https://www.youtube.com/watch?v=jSr6g3YgyH0

Skip to 4:40 to check it out

[circeseye]

i believes its 2 things..one 2.0 is cheaper..and two, the mobo connector for 2.0 is a lot smaller then 3.0

[Sorenson]

This is just a guess but processors generally have limited channels to the CPU, so maybe they didn't have enough bandwidth leftover for two usb 3.0 ports. 

[RoseLuck462]

3.0 is too fast for some people!

[Crunchy Dragon]

2 minutes ago, Sorenson said:

processors generally have limited channels to the CPU

What does this mean?

 

Which processor are you referring to?

[SpaceGhostC2C]

I wouldn't need it on a laptop, but I wish more desktop motherboards kept some USB 2.0 ports in the rear I/O panel. The reason is that USB 3.0 and above are not fully backward compatible (despite being supposed to be), and some devices that work on 2.0 don't work on USB3. 

 

[Radium_Angel]

4 minutes ago, Crunchy Dragon said:

What does this mean?

 

Which processor are you referring to?

I wonder if the poster wasn't thinking of PICE lanes...and getting things confused.

3 minutes ago, SpaceGhostC2C said:

and some devices that work on 2.0 don't work on USB3. 

 

I have several older USB 2.0 cards that don't play nice with 3.0. It's irritating.

[cluelessgenius]

14 minutes ago, circeseye said:

i believes its 2 things..one 2.0 is cheaper..and two, the mobo connector for 2.0 is a lot smaller then 3.0

but when theres both they already have a 3.0 chip on there.

 

cpu lanes sounds like a maybe i guess 

 

[BobVonBob]

7 minutes ago, cluelessgenius said:

but when theres both they already have a 3.0 chip on there.

 

cpu lanes sounds like a maybe i guess 

 

I'd suspect it's mainly cost. A USB 3 connector is very slightly more expensive than a USB 2 one, because a USB 3 connector has 5 extra contacts. It's like 3 cents more, but it's more.

[Stefan Payne]

Lower power requirements and consumption for USB2.0.

 

3.0 is specified for 1A

2.0 is specified for 0,5A

 

And also the driving power for the higher frequency. We're talking about like 10 times the transfer rate.

[Mira Yurizaki]

It's cheaper, it's simpler, it's well understood, and many peripherals don't need that much bandwidth anyway.

[Guest]

Some devices are only compatible with 2.0 and lower, while some devices need 3.0 to operate. Remember whilst they are the same port physically, they are different.

[ManuelNigrito]

2.0 is still the best in my opinion

[cluelessgenius]

17 hours ago, BobVonBob said:

I'd suspect it's mainly cost. A USB 3 connector is very slightly more expensive than a USB 2 one, because a USB 3 connector has 5 extra contacts. It's like 3 cents more, but it's more.

yeah its not like with cars where they expect 100 million units sold. notebooks get revised to frequently. so maybe on high volume model i could see it i guess but on top shelf this shouldnt be a thing. although i have literally fought with the higher up at a known car brand over 3 kilo  bytes and them requiring a chip costing 9 cents more. ...FOUGHT!!! 

i will never get the industire and maybe thats why im not a rich car company owning dick.

[Inversion]

There are a few reasons:

1. Cost - USB 2.0 is cheaper than USB 3.0 and companies care about the bottom line
2. Backwards compatibility - some USB 2.0 devices don't play well with USB 3.0 despite the latter being supposedly fully backwards compatible
3. Use case - In reality, a lot of people will use an external mouse on a laptop and that will probably be where people end up plugging in a mouse and if it's wireless, just leave the receiver plugged in.

Ultimately it doesn't make a whole lot of difference unless you really think you need to have 4 USB SSDs plugged in all the time doing file transfers. I only have 2 USB 3.0 ports on my laptop (and a 3.1 Type C) and I get on just fine.

[Mira Yurizaki]

6 hours ago, cluelessgenius said:

yeah its not like with cars where they expect 100 million units sold. notebooks get revised to frequently.

Cars get revised frequently too. My car is the last year where the base trim doesn't come with a fancy head unit. The next year the base trim came with one. And now the base trim of the model of my car comes with stuff you would've found on the higher end trims of yesteryear.

[cluelessgenius]

3 minutes ago, Mira Yurizaki said:

Cars get revised frequently too. My car is the last year where the base trim doesn't come with a fancy head unit. The next year the base trim came with one. And now the base trim of the model of my car comes with stuff you would've found on the higher end trims of yesteryear.

yeah but what i meant is the chipset doest change that frequently unless theres a problem.

[Mira Yurizaki]

1 minute ago, cluelessgenius said:

yeah but what i meant is the chipset doest change that frequently unless theres a problem.

If it's the critical electronics like the ECU or those that control safety features, then yeah, you shouldn't be changing them unless you have a damn good reason. If it's the non-critical stuff like the infotainment then... well if you can still use the same hardware then why not?

[TheElectronicGeek1]

They probably don't put 2.0 ports on products for this reason but some things don't work on usb 3.0 ports even if the cables are 2.0. Jailbreaking older iphones doesn't work on 3.0 at all. (not realizing this caused me to stay up for like 5 hours trying to get my 3gs to jailbreak) Some other old devices just don't like them either.