Recently I purchased ASUS X53SV laptop. I have made it dual boot system by Windows 7 and ubuntu. I have noticed that Nvidia Geforce GT 540M video driver does not working at all. also some of the function keys does not working. I noticed brightness buttons, SRT/VGA switcher and Insert button are working fine. But I am not able to set sound or switch touch pad on or off. Can you give me a brief idea why I am suffering from the above mentioned issue?