Hi, For RHEL4-U4-64bit, we can boot up kernel with ACPI enabled in BIOS whether we add the kernel parameter "acpi=off" or not; however kernel can't boot with ACPI disabled in BIOS whether we add kernel parameter "acpi=off" or not. My question is, is there any difference between disabling ACPI in BIOS and acpi=off from the kernel's point of view? Thanks, Forrest - 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