power manager dosent work in eee pc 1005ha

i have asus eee pc running ubuntu desktop 10.10.
the power manager application dosen't have any effect on my netbook,
i ask for it to never shut off display or dim the screen or go into standby and it still continues doing it,
i tried to use "Make Default" and it didn't change a thing.
its kinda annoying i need to keep my eyes on the screen all the time to check that the netbook didn't go into standby.
any help or lead to solving this problem will be welcome.
btw i tried to do `cat /proc/acpi/ac_adapter/AC/state` like someone suggested in ask ubuntu and receive the following answer from the terminal `cat: /proc/acpi/ac_adapter/AC/state: No such file or directory` maybe that the problem :\