welcome Xavius! it was a coincidence that i replied both questions.
so, to check what you are running there is not a standard answer.
let's try that. please, post the ouput of:
this can also be BIOS dependent. some BIOS uses APM, that IMHO is worst than ACPI. But anyway we need to check what is up in your system.
about kde, i am sorry. i know sh*** about that. i just hope that kde has no applications that are using your power management. you can check that try another DE. Ex. wmaker, fluxbox,etc.
the ouput of dmesg is fundamental. it is important to see which modules are being loaded by the kernel.
i am not an expert. like *almost everybody* here i am a newbie. i just tried to help you to put better boundary conditions to your problem.
hope some guru join us here.