kernel /boot/vmlinuz26 root=/dev/discs/disc0/part4 ro acpi=force
Although it may not work for you because your system seems to have problems with acpi. Anyway, if the above solutions don't work, you can always try this one. It did the trick for me.
Try the following in your grub boot line in /boot/grub/menu.lst:
apm=power-off
Regards,
Win
]]>Every time i want to poweroff power is stil on and i have to manualy power off
in my grub.lst i have added acpi=off because my computer hangs with out this line
help needed
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