Ok, thanks.
You can fix this issue completely by switching to XP, or waiting for a new drivers from ATI (this may take an year, due to this company so slow...).
LightConverse 305 is not use Shader Model 3.0, that why it works on your system. Version 307 has completely new drawing engine. Unfortunately ATI just declared SM3.0 compatible but realization is buggy and works well on XP only. We spent a lot of time to find a solution for this, and finally decide to implement an emulation through the SM2.0 in future version for this type of system. Sure, emulation will be much slower.
So, my advice for now is use XP !
