# How can I know the USB version ?



## Peter Kent (Feb 3, 2005)

Hi!

I intend to install an external HD via USB for purposes of back-up. I found two models that fit to USB 2.0 and USB 1.1. My computer has two USB ports but I don't have any documents describing these ports; I've been connecting to them my digital camera and pendrives successfuly.

My questions are:

1. Is there any programs that show a description of the USB ports?

2. What kind of concerns should I have using external HD via USB? (speed, security, ?) [using WIN XP SP2]

Thank you,

Peter


----------



## UncleMacro (Jan 26, 2005)

If your computer has only two built-in USB ports then they are likely to be USB 1 ports. You can check for sure by checking in the *Device Manager* (open the *Control Panel*, double-click *System*, select the *Hardware* tab, click *Device Manager...* button). Check under *Universal Serial Bus Controllers*. There are different kinds of "host controllers": OHCI (open host controller - USB 1), UHCI (universal host controller - USB 1), and EHCI (enhanced host controller - USB 2). If you have USB 1 then you'll have OHCI or UHCI only. If you have USB 2 then you'll have OHCI or UHCI and you'll also have EHCI.

If you try to connect an external hard disk to a USB 1 port then you are limited to 1.5MB/sec versus connecting it to a USB 2 port which is usually about 30MB/sec or so for a hard disk. The USB 1 connection would be _very_ slow. So if you have only USB 1 ports then it would be worth it to get a cheap USB 2 expansion card and hook the hard disk to that instead. In most cases, USB 2 external hard disks can be connected to both USB 1 ports and USB 2 ports. They just slow down (a lot) when connected to a USB 1 port.


----------



## Peter Kent (Feb 3, 2005)

Hi, UncleMacro!

Thanks for your answer; you made it absolutely clear for me.
Service tab shows that my connections are OHCI, then USB 1. So I'll think about another kind of external HD.
Thank you,

Peter


----------



## Terrister (Apr 18, 2005)

Just add a PCI USB card. That will give your computer 2.0 usb.


----------



## Midnight Tech (Dec 31, 2001)

Just out of curiousity, does your machine have Firewire ports? If it does, this might be an alternative.... if not, I'd get that 2.0 add-in card.


----------



## Peter Kent (Feb 3, 2005)

My machine doesn't have any FireWire ports. I'll get a 2.0 add-in.

Thanks a lot for the answers,

Peter


----------

