Change the brightness of the display (C #)

Possible duplicate:
C # Windows 7 settings screen brightness

I searched the Internet for some topics on how to color the display brightness through C #.
For the most part, I got links to change gamma on Windows ( here and here ), and this works great for me. But I was wondering if this is the right way to dim or darken the display (does it save power as it reduces the brightness of the monitor?)

Is this a good way to dim or is there a better way to do the same? I am on Windows 7 (I forgot what the default gamma value is for Windows?) Anyone?)