T400, W7 64 bit: Setting brightness on discrete gfx no-go

[turantelle]

Problem: Can't change display brightness using discrete (ATI) graphics, works fine on integrated and switching also works (the brightness level on discrete is the one I set with the integrated).

Installed the windows update ATI drivers, and after that the latest power management driver and tool from lenovo (didn't work before installing these).

My bios is 1.19, could it be fixed with a bios upgrade? (but then I would have to change my wifi card as my current bios is hacked to accept all wifi cards).