My laptop only boots with the acpi=off parameter. How can I fix this?

view full story

http://askubuntu.com – I managed to install Ubuntu 12.10 with the option acpi=off, as it didn't work without. Now it boots only with this option. Is it possible to solve the problem for the need of this option? With this option it is booting is quite slow. Could it be related to the Nvidia GeForce GT 520M card I have with Optimus technology? Maybe its drivers? My laptop is a one year old ASPIRE 5750G. EDIT 12-1-2012: I finally solved the problem following the instructions given by Arttu at the question Desktop does not show when I installed nvidia drivers!. The problem was about the nvidia drivers. (HowTos)