After Upgrading up Ubuntu, and installed the additional drivers, and i tried bot the options that I got, and the brightness key do not work. What I mean by not working is that it shows me the bar as to it is moving up and down, but it does not change the display brightness. Any way to fix this.
From this wiki page http://www.thinkwiki.org/wiki/Category:W510
Append the following in Device section to your xorg.conf and restart X.
Option "RegistryDwords" "EnableBrightnessControl=1"
The page has additional tips on the w510
If someone looking for a new answer : just upgrade BIOS to last lenovo version, and Brightness control will work .