I have aspi_osi=Linux tried and thinks look better this way. I saw this message in the /var/log/messages. My operating system : Ubuntu 8.10 [ 0.496839] ACPI: DMI System Vendor: Dell Inc. [ 0.496840] ACPI: DMI Product Name: Inspiron 1721 [ 0.496842] ACPI: DMI Product Version: [ 0.496843] ACPI: DMI Board Name: 0UK441 [ 0.496845] ACPI: DMI BIOS Vendor: Dell Inc. [ 0.496846] ACPI: DMI BIOS Date: 04/21/2008 With kind regards, Tom Kaalverink -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html