I just refreshed my laptop hardware. I installed everything but realized that I couldn’t dim the screen. After some searching, people had all sorts of zany registry hacks.
In the end though, I saw some posts that were talking about making sure you had the latest video card drivers. When I looked, I didn’t – I had the default Windows driver. I downloaded the correct drivers and voila! My brightness now works.
The lesson here is that the brightness controls in Windows 8 are handled by the video card drivers – I didn’t know that!