Problem with USB 2.0

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Revision as of 11:53, 10 May 2005 by 217.231.106.144 (Talk)

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Problem description

On various (early?) T40 models, USB 2.0 may not function. Symptoms include inability to connect to USB 2.0 devices at USB 2.0 speeds, the "This device can perform faster" pop-up in Windows XP, device ID assignment error messages from the Linux kernel, and frequent reboots of the USB bus and connected devices.

Affected Models

Solutions

This seems to be a hardware problem with the USB controller on Intel's chip or related electronics. Sending the laptop in for service may help.

If the Linux kernel refuses to register the USB device, "modprobe -r ehci_hcd" may help. This disables USB 2.0 functionality for the session.