I've been trying to resolve this for months. Several posts describe Intel HD 3000/4000 latest drivers, in my case 9.17.10.2875 (Oct 17, 2012) drivers as failing on being able to change display brightness on laptop's LCD, with always running on MAX brightness. I've tried the standard fixes of On/Off of Adaptive Display, BIOS updates, and so far I've found nothing that works on AC or on battery.
Lots of folks are reporting this if you BING (and here) on the problem.
Any thoughts?
Thanks,