USB 2 and USB 3 Ports On New Desktops: Why Have Both ?

[Robert11]

Hello,

Have been looking at some new Desktops, and it seems HP, Dell, and some others have
both USB 2 and USB 3 Ports built in.

Question: If USB 3 is truly and fully backward compatible, whey the need for the USB 2 ?
Why not just have all USB 3 ?

Is it to save a few cents in the implementation ?
Or,...?

And, 4 Ports on many, even the pricier ones, isn't very many.
Does a powered USB Hub work, usually, very well, and easily makes up for the deficiency ?
Any caveats, etc. ?

Thanks,
Bob

 

[GokAy]

Some mobos won't use the USB3 ports on bootup, and there are some legacy USB issues even though it is supposed to be compatible. So I believe it is a mix of compatibility, operability and cost reduction.

 

[Lady Fitzgerald]

Some mobos won't use the USB3 ports on bootup, and there are some legacy USB issues even though it is supposed to be compatible. So I believe it is a mix of compatibility, operability and cost reduction.

Gokhan pretty much nailed it.

 

[PBzeer]

I use a Toshiba Dynadock USB hub, primarily for an external monitor and 5.1 sound for my two laptops. It has 4 3.0 ports and 2 2.0. So far, it has worked well.

 

[OvenMaster]

I've got a Philips GoGear ViBE mp3 player/FM radio that works great with USB 2 ports, but my USB 3 ports don't even see it.
My Xbox 360 wired controller and my new Canon LiDE scanner both see the USB 2 and 3 ports and work fine.

 

[Layback Bear]

I can't give a technical reason but I do know that some things just don't work properly on 3.0. It could be the various bios or the drivers and when they load. My keyboards work better on 2.0 but the manufacture states they can be used on 3.0. Sometimes when using 3.0 the keyboards will not load on Startup.

 

[UsernameIssues]

...and then there is this:
USB-C has already won | The Verge

 

[Lady Fitzgerald]

Some of the incompatibility issues with USB 3.0 depends on where it comes from. USB 3.0 taken from the processor or a special chip usually do not have problems. USB 3.0 taken from PCI-e lanes will not work with mice and keyboards. Also, even though the USB 3.0 standards call for it, not all ports have the power that the standards call for. Some machines that have multiple USB 3.0 ports are actually connected to a hub running off a single USB 3.0 source and will have limited bandwidth and reduced power when used with more than one device.

I have two native USB 3.0 ports on my rear I/O panel. I had my AC Wi-Fi adapter plugged into one and a desktop two port USB 3.0 hub plugged into the other one (I wanted, needed, and now use only one port on my desk but the one port USB 3.0 desktop extensions I could find were both ugly and would have been awkward to use). For some wacky reason, one of my 8GB Kingston USB 3.0 thumb drives (I have several) took forever to be recognized when I plugged it into that hub but it worked fine in other USB 3.0 ports. I recently tried swapping the Wi-Fi adapter with the hub and, lo and behold, the logy, recalcitrant thumb drive now gets recognized immediately, same as my other ones do, and the Wi-Fi adapter still works just fine. Weird!

I have an internal card reader that also has three USB 3.0 ports that runs of a single PCI-e lane (it's essentially a hub; I use only one device at a time in it because of the limited bandwidth but, since all I use it for is reading camera cards, that's not a problem). Since it runs off PCI-e, everything I've plugged into it, both USB 2.0 and USB 3.0, works just fine but mice and keyboards will no work.

 

[Lady Fitzgerald]

...and then there is this:
USB-C has already won | The Verge

I have to laugh at those claims. Other than the connector being reversible (I still can't understand why that is such a big deal even though it obviously is), every new cable and connector type that came out pretty much made the same claims. And the same will be true of Type C when the next standard comes out that Type C will not be able to meet.

 

[Layback Bear]

Lady your post #8 said better what I was trying to say.

Their are things about 3.0/2.0 usb on different computers with different hardware being use that just are. Some times we don't know the reasons.
We just figure out what works best on our system and go for it.