Disclaimer First:

• I have gone thorugh these following threads here and followed all of
  their advice but none of them worked


• https://askubuntu.com/questions/74376/brightness-control-problem-on-sony-vaio-with-nvidia-gt-320m


• unable to change brightness settings in sony vaio e series laptop


• Brightness doesn't change on Sony laptop

Now the Problem

I have installed Ubuntu 12.10 (64bit) in this Sony Vaio laptop. After vanilla isntallation the brightness keys are working and I can see the brightness indictaor going up and down but it isn't having any effect on the real brightness of the device.

I have installed additional drivers too but that didn't solve the problem.
I can't seem to be able to change the brightness.

Anyone knows how I can fix this?