Novell LINUX ENTERPRISE DESKTOP 10 SP2 - DEPLOYMENT GUIDE 08-05-2008 Deployment Manual page 562

28.3.3 ACPI Tools
The range of more or less comprehensive ACPI utilities includes tools that merely display
information, like the battery charge level and the temperature (acpi, klaptopdaemon,
wmacpimon, etc.), tools that facilitate the access to the structures in /proc/acpi or
that assist in monitoring changes (akpi, acpiw, gtkacpiw), and tools for editing the ACPI
tables in the BIOS (package pmtools).
28.3.4 Troubleshooting
There are two different types of problems. On one hand, the ACPI code of the kernel
may contain bugs that were not detected in time. In this case, a solution will be made
available for download. More often, however, the problems are caused by the BIOS.
Sometimes, deviations from the ACPI specification are purposely integrated in the
BIOS to circumvent errors in the ACPI implementation in other widespread operating
systems. Hardware components that have serious errors in the ACPI implementation
are recorded in a blacklist that prevents the Linux kernel from using ACPI for these
components.
The first thing to do when problems are encountered is to update the BIOS. If the
computer does not boot at all, one of the following boot parameters may be helpful:
pci=noacpi
Do not use ACPI for configuring the PCI devices.
acpi=ht
Only perform a simple resource configuration. Do not use ACPI for other purposes.
acpi=off
Disable ACPI.
WARNING: Problems Booting without ACPI
Some newer machines (especially SMP systems and AMD64 systems) need ACPI
for configuring the hardware correctly. On these machines, disabling ACPI can
cause problems.
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