[ltp] usb 2.0 operating as usb 1.1
Christian Hauser
linux-thinkpad@linux-thinkpad.org
Sun, 19 Jun 2005 18:51:57 +0200
Matthias Himber wrote:
> Short answer: your southbridge is about to die, get your system board
> replaced. Hopefully its still under warranty.
>
> Long answer: a number of Intel chipsets for Pentium IV and Pentium M
> processors have a design flaw that makes the southbridge (which contains the
> USB host controllers) especially sensitive to static electricity. As a result
> there is a (small) risk that when plugging in or removing a USB device causes
> damage to the chip. Usually, the first symptom is broken USB 2.0, behaving in
> exactly the way you described (ie, works under Windows, but only after some
> waiting and as if it was connected to a USB 1.1 controller, not a USB 2.0
> one, and not at all under Linux unless you unload the USB 2.0 driver). This
> tends to lead to a completely dead chipset a short time later, so better get
> it serviced NOW.
> Incidentially, exactly this happened to me around last Christmas. Same
> Thinkpad model, too.
Thanks a lot Matthias, I have the same problem, but ignored it so far,
because I hardly ever use USB devices. But not that I know I'll get this
fixed before my warranty ends.
Christian