Re: ThinkPad T41 - Strange USB 2.0 behaviour

[Robert de Rooy <robert.de.rooy@gmail.com>]

Joel Becker wrote:
> On Thu, Jun 07, 2007 at 10:23:19PM +0200, Robert de Rooy wrote:
>   
> > On my ThinkPad T41 USB 2.0 behaves strange. Most USB 2.0 devices, refuse 
> > to function as such. Under Windows I get a message that I should plug 
> > the device into a USB 2.0 port (but it continues to function as USB 
> > 1.1), while under Linux I need to manually unload ehci-hcd before I can 
> > access the device.
> >
> > The strange thing is that these USB 2.0 devices used to work just fine, 
> > and still do on other machines. In addition I have one USB 2.0 memory 
> > key that still works fine (both under Windows and Linux).
> >
> > Now to be honest, I think this is a hardware problem, as I have had 
> > another T41p before that also suddenly no longer liked USB 2.0 devices, 
> > and if you search with Google you find other ThinkPad T41 users 
> > complaining about similar behaviour.
> >     
>
> 	Hardware problem.  You need a new system board.  I had this
> problem on my T41, devices would sometimes work, sometimes not
> (depending on the reboot).  If I plugged in a USB 1.1 hub, then pluged
> the memory reader into the hub, it would always work at 1.1 speeds.
> 	New system board, USB 2.0 works just fine.
>
> Joel
>   
Yes I figured it was a hardware problem, but that was not really the 
point I was trying to raise ;). I would like, if possible for Linux to 
automatically fallback to USB 1.1 like Windows does (preferably with a 
suitable warning).

Regarding getting the systemboard replaced, this machine is already 
scheduled for replacement, and I should be getting a new one in the next 
few weeks. But other users apparently have been having similar problems, 
and might not want to get the (presumably out-of-warranty) systemboard 
replaced.
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