severity 689420 grave thanks Now the system does not boot even when acpi=off. It always stops booting somewhere in the middle. To make it sometimes (!) boot, one has, in addition to acpi=off, to make grub wait more than the obligatory 4 seconds. And even after that, some connected hardware does not work at all or does not work properly: external modem, touchpad, touck stick. This makes the package relatively useless. Thus, raising the severity.