[The Skeptic]

Hi everyone.

In the Device Manager, under USB Controllers, I find the following list:

3 x USB open host controller
1 x pci to USB enhanced host controller
1 x USB printing support
4 x USB root hub

looks like a shopping list but the truth is that I don't know what USB version in supported at each connection. The computer has 6 USB connectors (probably with extra 2 not showing outside the box). It has a USB ADSL modem and a USB printer connected.

My question is: Are all the connections the same, meaning, supporting USB 2.0 or is there a mix of connections, some supporting USB 1.1 and some supporting USB 2.0. If this is the case how do I know which is what?

Motherboard is MSI 661FM2 series, SIS 661FX Chipset Based. CPU is Celeron 2.4.

Thanks

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Hi v.a

I've had a quick look at the manual for your motherboard & it states that all the USB controllers are v2.0

[Samm]

Hi v.a

I've had a quick look at the manual for your motherboard & it states that all the USB controllers are v2.0

[The Skeptic]

Thanks, Sam.

The truth is that I looked in the manual but couldn't make up my mind about the question I brought up. It didn't make sense to me to have a mix of connectors since USB 2.0 also support 1.1. On the other hand the "open host controllers" and "enhanced host controllers"confuse me. Frankly, up to this point I don't understand what they mean, exactly.'

Thanks again, Sam.

[Samm]

It is extremely confusing, I agree.
Basically, Enhanced (EHCI) USB is USB v2.0 and Open (OHCI) USB or Universal (UHCI) USB support USB v1.1 & V1.0.
The reason you have both EHCI & OHCI present is for backwards compatibility with USBv1.1 devices.

The link below is to a Microsoft article about USB versions which you may find helpful :

http://www.microsoft...BFAQ_intro.mspx

[The Skeptic]

Thanks again,Sam.

I thought that USB 2.0 is a standard which is inherently built to support previous versions of USB without extra hardware or software, just like, as an analogy, NTFS support FAT 32. Hence my confusion.

I'll read what you suggested. It's a pleasure to work with you.

[Kurt_Aust]

Note that while all the USB controllers on the motherboard are 2.0, it may not be that way at the front end. Specifically the cabling used for the front USB connections on your case will determine if those ports are 2.0 or 1.1 compliant.

If the cable has all four wires going into one large (shielded) cable then you've got 2.0, if they're just seperate wires runing to the front then it will probably be recognised as 1.1

[The Skeptic]

Thanks very much KURT_AUST.

Your post brings me back to the point where I started pondering about the USB connections:

1: If all the controllers are USB 2.0 and support USB 1.1 why would some of them be 1.1 which doesn't support USB 2.0? What's the point in that?

2: Is there a way to know which connector is what without opening the box? How do a user supposed to know which is what?


The truth is that Sam's answer makes sense to me because it simplifies things and makes them logical. However, we deal here with facts and these are not easy to interprate at the moment.

Thanks again. I'll probably have to write to MSI's support team to have a definite answer.


Ami Yogev

[Kurt_Aust]

If the USB ports on the front of your case are limited to USB 1.1 by the cabling inside your case, MSI won't be able to help you. It's not like they have any control over what case the retailer put the motherboard into when making up your computer.

Your USB ADSL modem and printer will not limited by the 1.1 speed of 12MB/s in any case. The easiest way to check the speed of your USB ports is to connect a mass storage device to each of them in turn, either a USB hard drive or flash memory stick. If the port is only USB 1.1, XP will throw up a message along the lines of "This device can go faster if you connect it to a USB 2.0 compliant port".

[The Skeptic]

If I understand correctly the 4 ports at the back of the computer are USB 2, being part of the motherboard, and the 2 at the front can also support USB 2 provided the cables are the right ones. By the way, I started this topic after I used USB HD for backuping jobs and found inconsistencies which I couldn't explain.

Thank

[Kurt_Aust]

That would be right , if it's fast when connected to the back and s.l..o...w when connected to the front, it's almost certainly due to a limitation from the case's internal cabling.

[The Skeptic]

thanks / Ami Yogev