Hi Mike

Thanks for the info. The hub that I was having the problem with is an
un-powered one.

However, after some trawling about on the net, I discovered that, by
default, in Windows XP, the USB ports attached to the motherboard have a
Power Management facility switched ON. Unfortunately, as Microsoft know,
it doesn't always reset completely when you send something to the
printer or whatever, but only when you use a hub, equipment plugged into
"original" ports are ok.

By de-selecting this option manually via Device Manager; USB Root;
Properties; Power Management, the ports don't "go to sleep" and thus the
problem disappeared.

It worked for me and when I told our IT lads at work, they had never
heard of this, so I don't think it's well documented.

Best regards,    Pete Sowerby......
>
> From: [log in to unmask]
> Date: 2004/02/03 Tue PM 06:38:34 GMT
> To: [log in to unmask]
> Subject: Re: [PCBUILD] USB Hub Problems
>
> Pete,
>
> Is your USB hub self powered or bus powered?  Check the power required for
> your devices.  Make sure your not drawing more power than the port can supply if
> it is bus powered.  Always use the separate power supply if possible for your
> hub.
>
> Does your motherboard BIOS support USB 2.0?  I am not positive in XP but I
> know in W2K you have a fixed amount of bandwidth to share.  What is the speed
> required for your printer and camera.  Could this be your issue?
>
> Regards,
> Mike Scott
>
>                   Visit our website regularly for FAQs,
>                articles, how-to's, tech tips and much more
>                           http://freepctech.com
>

-----------------------------------------
Email provided by http://www.ntlhome.com/

            Do you want to signoff PCBUILD or just change to
                    Digest mode - visit our web site:
                   http://freepctech.com/pcbuild.shtml